Health Education Systems Inc (HESI) A2 Exam Quiz: Roman Numerals
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Roman NumeralsQuestion 1 of 20

A medical center's budget allocated MMD dollars for equipment purchases. They spent DCCLX dollars in the first quarter and CDXC dollars in the second quarter. How much remains for the final two quarters combined?

$2,000 remaining for final quarters
$1,500 remaining for final quarters
$750 remaining for final quarters
$1,250 remaining for final quarters
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Health Education Systems Inc (HESI) A2 Exam Quiz

Health Education Systems Inc (HESI) A2 Exam Quiz: Roman Numerals

Practice Roman Numerals in Health Education Systems Inc (HESI) A2 Exam with focused quiz questions that help you check what you know, review explanations, and build confidence with test-style prompts.

What this quiz covers

This quiz focuses on Roman Numerals, giving you a quick way to practice the rules, question types, and explanations that matter most for Health Education Systems Inc (HESI) A2 Exam.

How to use this quiz

Try each quiz question before looking at the correct answer. Use the explanations to review missed ideas, then come back to similar questions until the pattern feels familiar.

All questions

Question 1

A medical center's budget allocated MMD dollars for equipment purchases. They spent DCCLX dollars in the first quarter and CDXC dollars in the second quarter. How much remains for the final two quarters combined?

  1. $2,000 remaining for final quarters
  2. $1,500 remaining for final quarters
  3. $750 remaining for final quarters
  4. $1,250 remaining for final quarters (correct answer)
Explanation: When you encounter Roman numeral problems in healthcare settings, you're being tested on both numerical conversion skills and basic arithmetic operations that are essential for dosage calculations and budget management. First, convert the Roman numerals to standard numbers: MMD = 2000 + 500 = 2,500 dollars allocated; DCCLX = 500 + 200 + 50 + 10 = 760 dollars spent in Q1; CDXC = 400 + 90 = 490 dollars spent in Q2. Now calculate the remaining budget: Total spent in first two quarters = $760 + $490 = $1,250. Amount remaining = $2,500 - $1,250 = $1,250. Looking at the wrong answers: Choice A (2,000)incorrectlysubtractsonlyonequarter′sspending,likelyjustthesmallerQ2amount(2,000) incorrectly subtracts only one quarter's spending, likely just the smaller Q2 amount (2,500 - $490 = 2,010,rounded).ChoiceB(2,010, rounded). Choice B (1,500) appears to result from miscalculating the Roman numerals—perhaps reading DCCLX as 650 instead of 760 ($2,500 - $650 - $490 = 1,360,approximately).ChoiceC(1,360, approximately). Choice C (750) represents a significant calculation error, possibly confusing the remaining amount with one of the quarterly spending amounts. The correct answer is D: $1,250 remaining for the final two quarters. For HESI success, practice Roman numeral conversions until they're automatic—you'll see them in medication problems and historical medical contexts. Always double-check your arithmetic by working backwards: does $1,250 remaining + $1,250 spent = $2,500 allocated? Yes, confirming our answer.

Question 2

Calculate the result of the following operation and express the answer as a Roman numeral: DCCCXL - CDXC

  1. CCCV
  2. CCCL (correct answer)
  3. CDLV
  4. CDLX
Explanation: When you encounter Roman numeral arithmetic on the HESI, you need to convert to Arabic numerals, perform the calculation, then convert back to Roman numerals. First, let's convert each Roman numeral to Arabic numbers. DCCCXL breaks down as: D (500) + CCC (300) + XL (40) = 840. CDXC breaks down as: CD (400) + XC (90) = 490. Remember that when a smaller numeral appears before a larger one, you subtract it. Now perform the subtraction: 840 - 490 = 350. Next, convert 350 back to Roman numerals. Break it down by place value: 300 + 50. For 300, you write CCC (three hundreds). For 50, you write L. Therefore, 350 = CCCL. Looking at the wrong answers: Choice A (CCCV) equals 305, which would result from incorrectly calculating 840 - 490 as 305 instead of 350. Choice C (CDLV) equals 455, suggesting an addition error (840 + 490 = 1330, then possibly misreading). Choice D (CDLX) equals 460, which might come from calculation errors in the subtraction process. The correct answer is B (CCCL = 350). For Roman numeral success on the HESI, always work systematically: convert to Arabic numerals first, do your arithmetic carefully, then convert back. Double-check by converting your final Roman numeral answer back to Arabic to verify it matches your calculated result.

Question 3

A pharmacist needs to divide a stock of MCCL mg of a medication into L equal doses. How many milligrams are in each dose? Express the answer as a Roman numeral.

  1. XXIII
  2. XXV (correct answer)
  3. XXVI
  4. XXX
Explanation: When you encounter dosage calculation problems on the HESI, you're working with basic division and unit conversion. This question tests your ability to divide medication quantities and express answers in Roman numerals. To find the dose per unit, you need to divide the total stock by the number of doses: MCCL mgL doses\frac{\text{MCCL mg}}{\text{L doses}} First, convert the Roman numerals to Arabic numbers. MCCL = 1000 + 200 + 50 = 1,250 mg, and L = 50 doses. Now calculate: 1,250 mg50 doses=25 mg per dose\frac{1,250 \text{ mg}}{50 \text{ doses}} = 25 \text{ mg per dose} Converting 25 back to Roman numerals: 25 = XXV (10 + 10 + 5). Looking at the wrong answers: A) XXIII represents 23 mg, which would result from calculation errors in either the Roman numeral conversion or the division. C) XXVI represents 26 mg, likely from rounding errors or misreading the Roman numerals. D) XXX represents 30 mg, which could come from incorrectly calculating L as 40 instead of 50, giving you 1,250 ÷ 40 = 31.25, then rounding to 30. The correct answer is B) XXV, representing 25 mg per dose. For HESI success, practice converting between Roman and Arabic numerals until it's automatic, and always double-check your division with simple multiplication (25 × 50 = 1,250 ✓). Remember that medication calculations require precision—small errors can have serious consequences in healthcare settings.

Question 4

A patient is prescribed VI pills per day for IX days. What is the total number of pills the patient will take? Express the answer as a Roman numeral.

  1. XV
  2. LIV (correct answer)
  3. LVI
  4. LX
Explanation: Roman numeral calculations appear regularly on the HESI exam, testing your ability to work with this historical number system used in medical contexts like medication schedules and dosing protocols. To solve this problem, you need to multiply VI (6) pills per day by IX (9) days. First, convert the Roman numerals to Arabic numbers: VI = 5 + 1 = 6, and IX = 10 - 1 = 9. Then multiply: 6 × 9 = 54 pills total. Finally, convert 54 back to Roman numerals: 54 = 50 + 4 = L + IV = LIV. Looking at the wrong answers: A) XV equals 15, which would be the result if you mistakenly calculated VI + IX (6 + 9) instead of multiplying them. C) LVI equals 56, which you might get if you incorrectly wrote 54 as L + VI instead of L + IV—a common error when forgetting that IV represents 4, not VI. D) LX equals 60, which could result from miscounting the days or pills, perhaps thinking it was 10 days instead of 9. The correct answer is B) LIV, representing 54 total pills. Remember this key strategy for Roman numeral problems on the HESI: always convert to Arabic numbers first, perform your calculations, then convert back to Roman numerals. Also, watch for subtraction cases like IV (4) and IX (9) where a smaller numeral precedes a larger one. Practice recognizing common medical Roman numerals like dosing amounts (I-X) and larger numbers (L=50, C=100) since these appear frequently in healthcare settings.

Question 5

A surgical procedure is scheduled to take CXXV minutes. If the procedure must end by IV P.M., what is the latest time it can begin?

  1. 1:55 P.M. (correct answer)
  2. 2:05 P.M.
  3. 2:35 P.M.
  4. 2:55 P.M.
Explanation: When you encounter time calculation problems on the HESI, you need to work with Roman numerals and perform backward time calculations. This question tests both skills simultaneously. First, convert the Roman numeral: CXXV = 100 + 20 + 5 = 125 minutes. To convert to hours and minutes, divide by 60: 125 ÷ 60 = 2 hours and 5 minutes (since 125 = 2 × 60 + 5). Since the procedure must end by 4:00 P.M. and takes 2 hours 5 minutes, work backward: 4:00 P.M. - 2 hours 5 minutes = 1:55 P.M. This makes A) 1:55 P.M. correct. Looking at the wrong answers: B) 2:05 P.M. would result in the procedure ending at 4:10 P.M. (2:05 + 2:05 = 4:10), which is 10 minutes too late. C) 2:35 P.M. would end at 4:40 P.M. (2:35 + 2:05 = 4:40), missing the deadline by 40 minutes. D) 2:55 P.M. would end at 5:00 P.M. (2:55 + 2:05 = 5:00), a full hour past the required end time. For HESI success, master common Roman numerals (I=1, V=5, X=10, L=50, C=100) and practice time arithmetic. When working backward from deadlines, always double-check by adding the duration to your calculated start time—it should equal the required end time. This verification step catches calculation errors and builds confidence in your answer.

Question 6

A medical encyclopedia consists of volumes numbered consecutively from Volume VII to Volume XLIII. How many individual volumes are in the complete set?

  1. 35
  2. 36
  3. 37 (correct answer)
  4. 38
Explanation: This question tests your ability to count consecutive items in a sequence, which appears on standardized tests to assess basic mathematical reasoning and attention to detail. To find how many volumes are in the set from Volume VII to Volume XLIII, you need to count all volumes including both endpoints. First, convert the Roman numerals: VII = 7 and XLIII = 43. The formula for counting consecutive integers from a starting number to an ending number is: (ending number - starting number) + 1. So: (43 - 7) + 1 = 36 + 1 = 37 volumes. The "+1" is crucial because you must include both the first and last volumes in your count. Think of it like counting from 1 to 5: the numbers are 1, 2, 3, 4, 5—that's five numbers, not four. Choice A (35) represents the error of subtracting without adding 1: 43 - 7 = 36, then mistakenly subtracting another 1. Choice B (36) is the most common mistake—simply subtracting the endpoints (43 - 7 = 36) but forgetting to add 1 to include both boundary volumes. Choice D (38) suggests adding 2 instead of 1, perhaps from confusion about how to handle the endpoints. When counting consecutive items in any sequence, always remember the formula: (last - first) + 1. This applies whether you're counting pages, chapters, volumes, or any numbered series. The key insight is that both endpoints are included in the count.

Question 7

The number 999 is correctly represented by which Roman numeral?

  1. IM
  2. CMXCIX (correct answer)
  3. DCCCCXCIX
  4. XDIX
Explanation: When you encounter Roman numeral questions on the HESI, remember that these symbols follow specific rules for combination and subtraction. The key is understanding how larger numbers are built using the subtractive principle. To convert 999 to Roman numerals, break it down by place value. Start with 900: this is represented as CM (1000 - 100 = 900, where C before M means subtract 100 from 1000). Next, 90 is written as XC (100 - 10 = 90, where X before C means subtract 10 from 100). Finally, 9 becomes IX (10 - 1 = 9, where I before X means subtract 1 from 10). Combining these parts gives you CMXCIX, making choice B correct. Choice A (IM) incorrectly attempts to represent 999 as 1000 - 1, but this violates Roman numeral rules. You can only subtract powers of 10 (I, X, C) from the next two higher values, and I can only be subtracted from V or X, never from M. Choice C (DCCCCXCIX) tries to write 900 as D + CCCC (500 + 400), but Roman numerals don't allow four consecutive identical symbols. This represents 899, not 999. Choice D (XDIX) incorrectly attempts to subtract X from D, which isn't allowed. X can only be subtracted from L or C, and this combination doesn't follow proper Roman numeral construction rules. Remember: Roman numerals use subtractive notation only with specific pairs (IV, IX, XL, XC, CD, CM), and you can never use more than three consecutive identical symbols.

Question 8

A historical medical text was published in the year MCMXCIX. A revised edition was published 25 years later. In which year, expressed in Roman numerals, was the revised edition published?

  1. MMXXIII
  2. MMXXIV (correct answer)
  3. MMXXV
  4. MMXXVI
Explanation: When you encounter Roman numeral problems on the HESI, you're being tested on both your ability to convert between number systems and perform basic arithmetic operations. These questions often appear in dosage calculations or historical contexts in healthcare. First, convert MCMXCIX to standard numbers. Break it down: M = 1000, CM = 900 (1000-100), XC = 90 (100-10), IX = 9 (10-1). So MCMXCIX = 1000 + 900 + 90 + 9 = 1999. Adding 25 years gives us 1999 + 25 = 2024. Now convert 2024 back to Roman numerals: 2000 = MM, 20 = XX, 4 = IV. Therefore, 2024 = MMXXIV. Looking at the wrong answers: Choice A (MMXXIII) represents 2023, which would be 24 years later, not 25. Choice C (MMXXV) represents 2025, suggesting you added 26 years instead of 25. Choice D (MMXXVI) represents 2026, indicating you added 27 years. These errors typically occur when students miscalculate the addition or make mistakes in Roman numeral conversion. Remember that IV = 4, not IIII, and that subtractive notation (like CM for 900) follows specific rules. For HESI success, practice converting years around 1900-2100 to Roman numerals, as these frequently appear in healthcare contexts. Always double-check your arithmetic when working with Roman numerals, and remember that healthcare dosage calculations may occasionally use Roman numerals, making this skill practically relevant to nursing.

Question 9

Which of the following Roman numerals is written incorrectly according to standard formation rules?

  1. XCIX
  2. CDXLIV
  3. VC (correct answer)
  4. CMIX
Explanation: Roman numeral questions test your understanding of proper formation rules, particularly the subtraction principle and valid letter combinations. When you encounter these questions, focus on which letters can be subtracted from which, and in what positions. Let's examine why C (VC) violates standard formation rules. In Roman numerals, V (5) can never be used as a subtractive prefix because only I, X, and C can subtract from larger values. Additionally, when subtracting, you can only subtract from the next two higher values in the sequence. Since V comes before C in the value hierarchy (I=1, V=5, X=10, L=50, C=100), placing V before C creates an invalid combination. The correct way to write 95 would be XCV (100-10+5). Looking at the other options: A (XCIX) correctly represents 99 using valid subtractions (100-10+10-1). B (CDXLIV) properly shows 444 with CD (400), XL (40), and IV (4) - all following correct subtraction rules. D (CMIX) accurately represents 1009 using CM (900) plus IX (9), both valid formations. The key trap here is that VC might seem logical if you think "5 before 100 equals 95," but Roman numeral subtraction follows strict rules about which letters can subtract and from what values. Study tip: Remember the subtraction rule acronym "IXC" - only I, X, and C can be subtractive prefixes, and they can only subtract from their next two higher denominations (I from V and X; X from L and C; C from D and M).

Question 10

What is the sum of the integers from VII to XI, inclusive? Express the answer as a Roman numeral.

  1. XL
  2. XLV (correct answer)
  3. L
  4. LV
Explanation: When you encounter Roman numeral problems, start by converting to Arabic numerals to make calculations easier, then convert back to Roman numerals for your final answer. First, let's convert the Roman numerals: VII = 7, VIII = 8, IX = 9, X = 10, and XI = 11. The phrase "inclusive" means we include both endpoints (7 and 11) in our sum. Now we calculate: 7 + 8 + 9 + 10 + 11 = 45. Converting 45 back to Roman numerals: since 40 = XL and 5 = V, we get XLV. Looking at the wrong answers: Choice (A) XL equals 40, which would be the sum if you forgot to include one of the endpoint values. Choice (C) L equals 50, which you might get if you miscounted the sequence or made an arithmetic error. Choice (D) LV equals 55, which could result from incorrectly including XII (12) in your sequence or making a calculation mistake. The key trap here is forgetting what "inclusive" means - it's crucial to include both VII and XI in your sum. Another common error is rushing through the Roman numeral conversions, especially with numbers like IX (9), where students sometimes confuse the subtraction rule. For Roman numeral questions on the HESI, always convert to Arabic numerals first for any calculations, double-check that you understand terms like "inclusive," and remember the basic subtraction combinations: IV (4), IX (9), XL (40), XC (90), CD (400), and CM (900).

Question 11

A medication dosage chart shows that for every X pounds of body weight, a patient should receive ii milligrams of medication. If a patient weighs LXXXV pounds, what is the correct total dosage?

  1. 8.5 milligrams total dosage
  2. 170 milligrams total dosage
  3. 17 milligrams total dosage (correct answer)
  4. 42.5 milligrams total dosage
Explanation: When you encounter medication dosage calculations with Roman numerals, you need to first convert the Roman numerals to Arabic numbers, then apply the dosage ratio. Let's decode the Roman numerals: X = 10 and ii = 2. So the dosage chart shows 2 milligrams per 10 pounds of body weight. The patient weighs LXXXV pounds, which breaks down as L (50) + XXX (30) + V (5) = 85 pounds. Now set up a proportion to find the total dosage: 2 mg10 lbs=x mg85 lbs\frac{2 \text{ mg}}{10 \text{ lbs}} = \frac{x \text{ mg}}{85 \text{ lbs}} Cross-multiplying: 2×85=10x2 \times 85 = 10x, so 170=10x170 = 10x, which gives us x=17x = 17 milligrams. Looking at the wrong answers: Choice A (8.5 mg) represents half the correct answer, likely from confusing 85 pounds as 42.5 or making an arithmetic error. Choice B (170 mg) is the result you'd get if you forgot to divide by 10 in the final step—this is the numerator before completing the proportion. Choice D (42.5 mg) suggests someone might have divided 85 by 2 instead of using the proper ratio calculation. Study tip: For HESI dosage calculations, always convert Roman numerals first, write out your proportion clearly, and double-check your arithmetic. Roman numeral questions often appear specifically to test whether you can accurately translate before calculating—practice recognizing common Roman numerals like L (50), X (10), V (5), and i (1) to build speed and confidence.

Question 12

A medication order specifies viii tablets to be administered over XXIV hours, with doses given every VI hours. How many tablets should be given in each individual dose?

  1. 1 tablet per dose
  2. 2 tablets per dose (correct answer)
  3. 3 tablets per dose
  4. 4 tablets per dose
Explanation: First convert the Roman numerals: viii = 8 tablets total, XXIV = 24 hours, VI = 6 hours. If doses are given every 6 hours over 24 hours, there are 24 ÷ 6 = 4 doses total. Therefore, 8 tablets ÷ 4 doses = 2 tablets per dose. Choice A assumes 8 doses instead of 4. Choice C incorrectly calculates 6 ÷ 2. Choice D assumes only 2 doses total.

Question 13

A medical facility's inventory shows XLVII units of supplies used in week one, XXXIV units in week two, and LII units in week three. If the target monthly usage should not exceed CXX units, by how many units did they exceed or stay under the target?

  1. Exceeded target by 13 units (correct answer)
  2. Stayed under target by 13 units
  3. Exceeded target by 7 units
  4. Met target exactly with 120 units
Explanation: XLVII = 47, XXXIV = 34, LII = 52, CXX = 120. Total usage = 47 + 34 + 52 = 133 units. Target = 120 units. Since 133 > 120, they exceeded by 133 - 120 = 13 units. Choice B reverses the direction (under vs. over). Choice C miscalculates the difference as 127 - 120. Choice D incorrectly assumes they met the target exactly.

Question 14

A treatment protocol requires IV cycles of therapy, with each cycle lasting XXI days. If treatments are given on days I, VIII, and XV of each cycle, how many total treatment days will occur throughout the entire protocol?

  1. 84 total treatment days
  2. 12 total treatment days (correct answer)
  3. 21 total treatment days
  4. 3 total treatment days
Explanation: When you encounter questions with Roman numerals in healthcare contexts, you're being tested on both your ability to convert Roman numerals and apply mathematical reasoning to treatment protocols. Let's decode the Roman numerals first: IV = 4 cycles, XXI = 21 days per cycle, and the treatment days are I = 1st day, VIII = 8th day, and XV = 15th day of each cycle. Now for the calculation: Each cycle has 3 treatment days (days 1, 8, and 15). With 4 total cycles in the protocol, you multiply: 3 treatment days per cycle × 4 cycles = 12 total treatment days. This confirms answer B is correct. Looking at the wrong answers: Answer A (84 total treatment days) likely comes from multiplying all the numbers together (4 × 21 = 84), but this represents the total days in the protocol, not just treatment days. Answer C (21 total treatment days) might result from confusing the cycle length with the number of treatment days, or incorrectly adding 21 to something else. Answer D (3 total treatment days) represents only the treatment days in a single cycle, ignoring that the protocol runs for 4 cycles. For HESI math problems involving medical protocols, always break down the problem systematically: identify what each number represents, determine what the question is actually asking for, and distinguish between total time periods versus specific intervention days. Roman numerals appear frequently in healthcare settings, so practice converting them quickly and accurately.

Question 15

A patient's fluid intake record shows XVI ounces at breakfast, XII ounces at lunch, XX ounces at dinner, and VIII ounces as snacks. If the daily target is LXIV ounces, what percentage of the target was achieved?

  1. 64% of daily target achieved
  2. 112.5% of daily target achieved
  3. 75% of daily target achieved
  4. 87.5% of daily target achieved (correct answer)
Explanation: This question tests your ability to convert Roman numerals and calculate percentages—two skills commonly assessed together on the HESI exam. When you see Roman numerals in healthcare contexts, you'll need to convert them to Arabic numbers before performing any calculations. First, convert each Roman numeral to find the actual fluid intake: XVI = 16 ounces (breakfast), XII = 12 ounces (lunch), XX = 20 ounces (dinner), and VIII = 8 ounces (snacks). The daily target is LXIV = 64 ounces. Total fluid intake = 16 + 12 + 20 + 8 = 56 ounces. To find the percentage: 5664×100=87.5%\frac{56}{64} \times 100 = 87.5\% Looking at the wrong answers: Choice A (64%) likely comes from confusing the target amount (64 ounces) with the percentage achieved. Choice B (112.5%) suggests someone may have flipped the fraction, calculating 6456×100\frac{64}{56} \times 100 instead of 5664×100\frac{56}{64} \times 100. Choice C (75%) might result from calculation errors in either the Roman numeral conversion or the percentage formula. The correct answer is D (87.5%). Study tip: When converting Roman numerals, remember that smaller numerals before larger ones are subtracted (IV = 4), while smaller numerals after larger ones are added (VI = 6). For percentage calculations in healthcare, always double-check that you're putting the actual value over the target value, not the reverse. Practice Roman numerals I through L, as these appear frequently on the HESI.

Question 16

A patient care schedule shows appointments at IX, XI, XIV, and XVII hundred hours. If each appointment lasts exactly XC minutes, how many minutes of break time exist between the second and fourth appointments?

  1. 180 minutes of break time (correct answer)
  2. 240 minutes of break time
  3. 60 minutes of break time
  4. 120 minutes of break time
Explanation: IX = 0900, XI = 1100, XIV = 1400, XVII = 1700. XC = 90 minutes. Second appointment starts at 1100 and lasts 90 minutes, ending at 1230. Fourth appointment starts at 1700. Between these times, the third appointment runs from 1400-1530 (90 minutes). Total time from end of 2nd to start of 4th = 1230 to 1700 = 4.5 hours = 270 minutes. Subtract the third appointment duration: 270 - 90 = 180 minutes of break time. Choice B doesn't account for the third appointment. Choice C only counts one break period. Choice D miscalculates the time intervals.

Question 17

A patient's chart shows vital signs recorded at XIV hundred hours and again IV hours later. If the second recording showed a temperature increase of ii degrees from the baseline of XCVII degrees, what was the temperature at the second recording?

  1. 95 degrees at 1800 hours
  2. 97 degrees at 1800 hours
  3. 99 degrees at 1800 hours (correct answer)
  4. 101 degrees at 1800 hours
Explanation: XIV hundred hours = 1400 hours (2:00 PM). IV hours later = 1400 + 4 = 1800 hours. Baseline temperature XCVII = 97 degrees. Temperature increase of ii = 2 degrees. Final temperature = 97 + 2 = 99 degrees at 1800 hours. Choice A subtracts instead of adds the increase. Choice B shows no temperature change. Choice D adds 4 degrees instead of 2.

Question 18

A prescription indicates that XV milliliters of medication should be divided equally among iii doses per day for vii days. What is the total volume of medication needed for the complete treatment?

  1. 105 milliliters total volume (correct answer)
  2. 35 milliliters total volume
  3. 21 milliliters total volume
  4. 5 milliliters total volume
Explanation: XV = 15 mL daily, iii = 3 doses per day, vii = 7 days. The 15 mL is the total daily amount (not per dose), so total needed = 15 mL/day × 7 days = 105 mL. Choice B calculates 5 mL per dose × 7 days, missing the 3 doses per day. Choice C calculates 15 ÷ 7 × 3. Choice D gives only the amount per individual dose (15 ÷ 3 = 5 mL).

Question 19

A laboratory result shows a white blood cell count of VII thousand per microliter, which represents a decrease from the previous count of XII thousand per microliter. What percentage decrease does this represent?

  1. Approximately 42% decrease from baseline (correct answer)
  2. Approximately 58% decrease from baseline
  3. Approximately 71% decrease from baseline
  4. Approximately 29% decrease from baseline
Explanation: VII = 7 thousand, XII = 12 thousand. Decrease = 12 - 7 = 5 thousand. Percentage decrease = (5/12) × 100% = 41.67%, approximately 42%. Choice B calculates the current value as a percentage of original (7/12 = 58%). Choice C uses the wrong denominator (5/7). Choice D calculates the decrease incorrectly as (5/17) instead of (5/12).

Question 20

Convert the Arabic numeral 1944 to its Roman numeral representation.

  1. MCMXXXXIV
  2. MCMXLIV (correct answer)
  3. MDCCCCXLIV
  4. MCMXLVI
Explanation: Roman numeral conversion questions test your understanding of the additive and subtractive principles that govern this ancient numbering system. When converting larger numbers like 1944, you need to break them down systematically using the standard Roman numeral values. To convert 1944, start with the largest values and work down: 1944 = 1000 + 900 + 40 + 4. In Roman numerals, 1000 = M, 900 = CM (1000 - 100), 40 = XL (50 - 10), and 4 = IV (5 - 1). This gives you MCMXLIV. The key principle here is that when a smaller numeral appears before a larger one, you subtract it. CM represents 900 (not 1100), XL represents 40 (not 60), and IV represents 4 (not 6). Looking at the wrong answers: Choice A (MCMXXXXIV) incorrectly represents 40 as XXXX instead of using the proper subtractive form XL. Choice C (MDCCCCXLIV) represents 1000 as M but then adds DCCCC (500 + 400) to make 900, which is unnecessarily complex when CM is the standard form. Choice D (MCMXLVI) correctly converts most of the number but ends with XLVI (46) instead of XLIV (44). Remember that Roman numerals follow specific subtractive rules: only I, X, and C can be subtracted, and only from the next two higher values (I from V or X, X from L or C, C from D or M). When you see conversion questions, always use the most efficient subtractive forms rather than adding extra symbols.