Elementary School Math Quiz: Add And Subtract Within 100
20 questions · exam conditions
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Add And Subtract Within 100Question 1 of 20

What is 67−1967 - 19?

38
58
49
48
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Elementary School Math Quiz

Elementary School Math Quiz: Add And Subtract Within 100

Practice Add And Subtract Within 100 in Elementary School Math 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 Add And Subtract Within 100, giving you a quick way to practice the rules, question types, and explanations that matter most for Elementary School Math.

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

What is 67−1967 - 19?

  1. 38
  2. 58
  3. 49
  4. 48 (correct answer)
Explanation: Subtracting 19 from 67 gives 48. Choice A is off by 10 from a regrouping mistake. Choice B mixes up which number to subtract from which. Choice C is off by 1 from a small counting error.

Question 2

Use the number line to add 27+3627 + 36.

  1. 53
  2. 62
  3. 63 (correct answer)
  4. 73
Explanation: This question tests 2nd grade understanding of adding and subtracting within 100, including using regrouping (carrying and borrowing) when necessary (CCSS 2.NBT.B.5: Fluently add and subtract within 100 using strategies based on place value, properties of operations, and/or the relationship between addition and subtraction; CCSS 2.NBT.B.7: Add and subtract within 1000, using strategies and algorithms based on place value—focus here on within 100). When adding two-digit numbers, add ones first, then tens. If the ones sum is 10 or more, regroup: write the ones digit and carry 1 ten to the tens column (example: 47 + 28 → 7 + 8 = 15, write 5 and carry 1 → 4 + 2 + 1 = 7 → answer is 75). When subtracting, subtract ones first, then tens. If the ones digit in the top number is smaller than the ones digit in the bottom number, regroup (borrow): take 1 ten from the tens column and add 10 to the ones (example: 63 - 27 → can't do 3 - 7, so regroup 6 tens 3 ones into 5 tens 13 ones → 13 - 7 = 6, 5 - 2 = 3 → answer is 36). Describe strategies: Place value strategy: Break numbers into tens and ones, add or subtract separately, combine (47 + 28 = 40 + 20 + 7 + 8 = 60 + 15 = 75). Number line: Start at first number, jump by tens then ones to add, or jump backward to subtract. In this problem, use the number line to add 27 + 36. To solve, start at 27, jump 30 to 57, then 6 to 63, or add ones: 7 + 6 = 13 (write 3, carry 1), tens: 2 + 3 + 1 = 6, answer 63. Choice C is correct because adding 27 + 36 correctly—7 + 6 = 13 (write 3, carry 1), 2 + 3 + 1 = 6, giving 63. This correctly applies addition with regrouping using number line strategy. Choice D represents not carrying when regrouping in addition (7 + 6 = 13 but wrote 53 instead of carrying to get 63, or basic fact error 7 + 6 = 12, giving 62). This error typically happens when students forget to regroup or misjump on the number line. To help students: Teach regrouping explicitly with place value understanding. For addition: 'When ones add to 10 or more, we have too many ones. Group 10 ones into 1 ten. Write the remaining ones, carry the 1 ten.' Use base-ten blocks: 4 tens + 7 ones + 2 tens + 8 ones → combine ones (7 + 8 = 15 ones = 1 ten + 5 ones), combine tens (4 + 2 + 1 = 7 tens) → 75. For subtraction: 'If top ones < bottom ones, we need more ones. Borrow 1 ten (= 10 ones) from tens column.' Show with blocks: 6 tens 3 ones, need to subtract 7 ones (can't), so trade 1 ten for 10 ones (5 tens 13 ones), now can subtract. Practice standard algorithm vertically—align place values, work ones first then tens. Teach number line strategy: to add, jump forward; to subtract, jump backward. For word problems, identify operation: 'got more, combine, total' = add; 'gave away, left, how many more' = subtract. Practice mental math strategies: break apart by tens and ones, use friendly numbers. Watch for: not regrouping when needed, regrouping incorrectly (carrying/borrowing wrong amount), place value errors, wrong operation for context, basic arithmetic mistakes.

Question 3

Add 24+3524 + 35. What is the total?

  1. 69
  2. 510
  3. 59 (correct answer)
  4. 49
Explanation: Adding 24 and 35 gives 59. Choice A, 69, comes from adding the tens digits incorrectly. Choice B, 510, comes from writing the digits side by side instead of adding them. Choice D, 49, comes from a small addition slip in the ones place.

Question 4

There were 78 students. 26 went home. How many are left?

  1. 54 (correct answer)
  2. 52
  3. 62
  4. 42
Explanation: This question tests 2nd grade understanding of adding and subtracting within 100, including using regrouping (carrying and borrowing) when necessary (CCSS 2.NBT.B.5: Fluently add and subtract within 100 using strategies based on place value, properties of operations, and/or the relationship between addition and subtraction; CCSS 2.NBT.B.7: Add and subtract within 1000, using strategies and algorithms based on place value—focus here on within 100). When adding two-digit numbers, add ones first, then tens. If the ones sum is 10 or more, regroup: write the ones digit and carry 1 ten to the tens column (example: 47 + 28 → 7 + 8 = 15, write 5 and carry 1 → 4 + 2 + 1 = 7 → answer is 75). When subtracting, subtract ones first, then tens. If the ones digit in the top number is smaller than the ones digit in the bottom number, regroup (borrow): take 1 ten from the tens column and add 10 to the ones (example: 63 - 27 → can't do 3 - 7, so regroup 6 tens 3 ones into 5 tens 13 ones → 13 - 7 = 6, 5 - 2 = 3 → answer is 36). Place value strategy: Break numbers into tens and ones, add or subtract separately, combine (47 + 28 = 40 + 20 + 7 + 8 = 60 + 15 = 75). Number line: Start at first number, jump by tens then ones to add, or jump backward to subtract. In this problem, there were 78 students and 26 went home, a word problem requiring subtraction to find how many are left. To solve, subtract 78 - 26: ones 8 - 6 = 2 (no borrow needed), tens 7 - 2 = 5, answer 52, or use place value: 70 - 20 = 50, 8 - 6 = 2, total 52. Choice C is correct because subtracting 78 - 26 correctly—8 - 6 = 2, 7 - 2 = 5, giving 52, or in context: 78 total, 26 left, 52 remain. This correctly applies subtraction without regrouping to the word problem. Choice B represents a wrong operation (perhaps added 78 + 26 = 104 but that's not an option, or miscalculated as 62 by borrowing unnecessarily or arithmetic error). This error typically happens when students confuse operations (add instead of subtract), make arithmetic mistakes, or don't understand word problem keywords like 'left'. To help students: Teach regrouping explicitly with place value understanding. For addition: 'When ones add to 10 or more, we have too many ones. Group 10 ones into 1 ten. Write the remaining ones, carry the 1 ten.' Use base-ten blocks: 4 tens + 7 ones + 2 tens + 8 ones → combine ones (7 + 8 = 15 ones = 1 ten + 5 ones), combine tens (4 + 2 + 1 = 7 tens) → 75. For subtraction: 'If top ones < bottom ones, we need more ones. Borrow 1 ten (= 10 ones) from tens column.' Show with blocks: 6 tens 3 ones, need to subtract 7 ones (can't), so trade 1 ten for 10 ones (5 tens 13 ones), now can subtract. Practice standard algorithm vertically—align place values, work ones first then tens. Teach number line strategy: to add, jump forward; to subtract, jump backward. For word problems, identify operation: 'got more, combine, total' = add; 'gave away, left, how many more' = subtract. Practice mental math strategies: break apart by tens and ones, use friendly numbers. Watch for: not regrouping when needed, regrouping incorrectly (carrying/borrowing wrong amount), place value errors, wrong operation for context, basic arithmetic mistakes.

Question 5

Maya has 52 beads and gets 19 more. How many now?

  1. 61
  2. 71 (correct answer)
  3. 70
  4. 81
Explanation: This question tests 2nd grade understanding of adding and subtracting within 100, including using regrouping (carrying and borrowing) when necessary (CCSS 2.NBT.B.5: Fluently add and subtract within 100 using strategies based on place value, properties of operations, and/or the relationship between addition and subtraction; CCSS 2.NBT.B.7: Add and subtract within 1000, using strategies and algorithms based on place value—focus here on within 100). When adding two-digit numbers, add ones first, then tens. If the ones sum is 10 or more, regroup: write the ones digit and carry 1 ten to the tens column (example: 47+2847 + 28 → 7+8=157 + 8 = 15, write 5 and carry 1 → 4+2+1=74 + 2 + 1 = 7 → answer is 75). When subtracting, subtract ones first, then tens. If the ones digit in the top number is smaller than the ones digit in the bottom number, regroup (borrow): take 1 ten from the tens column and add 10 to the ones (example: 63−2763 - 27 → can't do 3 - 7, so regroup 6 tens 3 ones into 5 tens 13 ones → 13−7=613 - 7 = 6, 5−2=35 - 2 = 3 → answer is 36). Place value strategy: Break numbers into tens and ones, add or subtract separately, combine (47+28=40+20+7+8=60+15=7547 + 28 = 40 + 20 + 7 + 8 = 60 + 15 = 75). Number line: Start at first number, jump by tens then ones to add, or jump backward to subtract. In this problem, Maya has 52 beads and gets 19 more, a word problem requiring addition. To solve, add 52+1952 + 19: ones 2+9=112 + 9 = 11 (write 1, carry 1), tens 5+1+1=75 + 1 + 1 = 7, answer 71, or use place value: 50+10=6050 + 10 = 60, 2+9=112 + 9 = 11, total 71. Choice B is correct because adding 52+1952 + 19 correctly—2+9=112 + 9 = 11 (write 1, carry 1), 5+1+1=75 + 1 + 1 = 7, giving 71, or in context: Maya had 52, got 19 more, total 71. This correctly applies addition with regrouping to the word problem. Choice A represents not carrying in addition (5+1=65 + 1 = 6, 2+9=112 + 9 = 11 but wrote 61 without proper carry or misadded). This error typically happens when students forget to regroup, make arithmetic mistakes, or confuse the operation in the word problem. To help students: Teach regrouping explicitly with place value understanding. For addition: 'When ones add to 10 or more, we have too many ones. Group 10 ones into 1 ten. Write the remaining ones, carry the 1 ten.' Use base-ten blocks: 4 tens + 7 ones + 2 tens + 8 ones → combine ones (7+8=157 + 8 = 15 ones = 1 ten + 5 ones), combine tens (4+2+1=74 + 2 + 1 = 7 tens) → 75. For subtraction: 'If top ones < bottom ones, we need more ones. Borrow 1 ten (= 10 ones) from tens column.' Show with blocks: 6 tens 3 ones, need to subtract 7 ones (can't), so trade 1 ten for 10 ones (5 tens 13 ones), now can subtract. Practice standard algorithm vertically—align place values, work ones first then tens. Teach number line strategy: to add, jump forward; to subtract, jump backward. For word problems, identify operation: 'got more, combine, total' = add; 'gave away, left, how many more' = subtract. Practice mental math strategies: break apart by tens and ones, use friendly numbers. Watch for: not regrouping when needed, regrouping incorrectly (carrying/borrowing wrong amount), place value errors, wrong operation for context, basic arithmetic mistakes.

Question 6

Keisha had 64 stickers and gave away 29. How many stickers did Keisha have left?

  1. 93
  2. 45
  3. 43
  4. 35 (correct answer)
Explanation: 64 minus 29 equals 35, so Keisha has 35 stickers left. 93 comes from adding instead of subtracting the two numbers. 45 comes from a regrouping mistake in the tens place. 43 comes from a smaller regrouping error in the ones place.

Question 7

Emma had some stickers. She gave 24 stickers to her sister and had 39 stickers left. Later, she bought 17 more stickers. How many stickers does Emma have now?

  1. 56 (correct answer)
  2. 80
  3. 63
  4. 22
Explanation: Emma had 39 stickers left after giving some away, and buying 17 more brings her total to 39 plus 17, which is 56. Eighty comes from adding all three numbers in the problem instead of just the two that apply. Sixty-three is how many stickers Emma had before she gave any to her sister, not her final amount. Twenty-two comes from subtracting instead of adding the stickers she bought.

Question 8

Sofia has 90 points and loses 38. How many points does she have left?

  1. 58
  2. 62
  3. 48
  4. 52 (correct answer)
Explanation: Subtracting 38 from 90 gives 52. Choice A, 58, does not match this subtraction. Choice B, 62, is too large for this difference. Choice C, 48, is close but off by a regrouping error.

Question 9

Ben scored 3838 points in his first game and 2727 points in his second game. Sarah scored 1919 more points than Ben's total. How many points did Sarah score?

  1. 84 (correct answer)
  2. 57
  3. 65
  4. 46
Explanation: Ben scored 38 + 27 = 65 points in total, and Sarah scored 19 more than that, so Sarah scored 65 + 19 = 84 points. Getting 57 comes from adding 19 only to Ben's first game instead of his total. Getting 65 is Ben's total, but it forgets to add the extra 19 points Sarah scored. Getting 46 comes from adding 19 only to Ben's second game instead of his total.

Question 10

Solve: 63−2763 - 27.

  1. 34
  2. 44
  3. 46
  4. 36 (correct answer)
Explanation: Subtracting 27 from 63 gives 36. Choice A, 34, is off by two from the correct difference. Choice B, 44, is too large for this subtraction. Choice C, 46, is also too large and likely comes from a regrouping error.

Question 11

Solve 74−3874 - 38.

  1. 46
  2. 36 (correct answer)
  3. 26
  4. 44
Explanation: The difference between 74 and 38 is 36, found by regrouping a ten to subtract the ones and then subtracting the tens. Choosing 46 suggests adding instead of subtracting the two numbers. Choosing 26 comes from a small subtraction error after regrouping. Choosing 44 comes from subtracting without regrouping, treating 4 minus 8 as if it were not possible, and then subtracting the tens incorrectly.

Question 12

There are 62 students. 27 go home. How many students are left?

  1. 35 (correct answer)
  2. 89
  3. 44
  4. 45
Explanation: Since 27 students go home, subtract: 62−27=3562 - 27 = 35. Choice B adds instead of subtracting. Choices C and D reflect small subtraction errors.

Question 13

Maya has 58 beads and gets 17 more. How many beads does Maya have now?

  1. 65
  2. 85
  3. 74
  4. 75 (correct answer)
Explanation: Maya starts with 58 beads and gets 17 more, so add 58 + 17 to get 75. Choice A, 65, is too small for this sum. Choice B, 85, is too large. Choice C, 74, is off by one from the correct total.

Question 14

Use place value to solve 56+3856 + 38.

  1. 94 (correct answer)
  2. 92
  3. 84
  4. 104
Explanation: Using place value, 50 plus 30 is 80 and 6 plus 8 is 14, and 80 plus 14 gives 94. Choice B, 92, comes from a small addition slip in the ones place. Choice C, 84, comes from miscombining the tens and ones. Choice D, 104, comes from adding an extra ten.

Question 15

What is 36+2936 + 29?

  1. 55
  2. 75
  3. 65 (correct answer)
  4. 64
Explanation: 36 plus 29 equals 65, which is the correct sum. Choosing 55 comes from a small addition error, ten less than the correct total. Choosing 75 comes from a small addition error, ten more than the correct total. Choosing 64 is just one less than the correct sum, a minor counting mistake.

Question 16

Ben used the number line shown to solve a subtraction problem. Refer to the number line below. What subtraction problem did Ben solve?

  1. 83−47=3683 - 47 = 36 (correct answer)
  2. 83−37=4683 - 37 = 46
  3. 83−46=3783 - 46 = 37
  4. 36+47=8336 + 47 = 83
Explanation: Ben starts at 3636 and jumps forward +4+4 to 4040, then +40+40 to 8080, then +3+3 to 8383. Total jumped: 4+40+3=474+40+3 = 47. So he solved 83−47=3683 - 47 = 36. Choice B miscounts the total jumps. Choice C swaps the difference and subtrahend. Choice D is an addition equation, not the subtraction problem asked for.

Question 17

Start at 52, move 18 spaces to the left, then move 25 spaces to the right. Where do you end up?

  1. At 59 (correct answer)
  2. At 61
  3. At 95
  4. At 34
Explanation: Starting at 52 and moving 18 to the left gives 34, then moving 25 to the right gives 59. Choice B, 61, does not match this two-step move. Choice C, 95, is much too large for these moves. Choice D, 34, only accounts for the first move and stops before the second one.

Question 18

In Week 1, students read 42 books. In Week 2, students read 47 books. What is the total number of books read during both weeks?

  1. 89 books (correct answer)
  2. 67 books
  3. 91 books
  4. 47 books
Explanation: Adding the 42 books from Week 1 and the 47 books from Week 2 gives a total of 89 books read during both weeks. Getting 67 or 91 usually comes from a small addition mistake. Getting 47 only counts the books read in Week 2 and leaves out Week 1 entirely. Adding both weeks together, not just one, gives the correct combined total of 89.

Question 19

What is 35+2935 + 29?

  1. 64 (correct answer)
  2. 63
  3. 54
  4. 74
Explanation: 35 plus 29 equals 64, which is the correct sum. Choosing 63 or 54 reflects a small addition or regrouping error near the correct answer. Choosing 74 comes from adding the tens digits incorrectly, off by a full ten from the correct sum.

Question 20

Use the number line to add 34+2734 + 27.

  1. 71
  2. 62
  3. 51
  4. 61 (correct answer)
Explanation: This question tests 2nd grade understanding of adding and subtracting within 100, including using regrouping (carrying and borrowing) when necessary (CCSS 2.NBT.B.5: Fluently add and subtract within 100 using strategies based on place value, properties of operations, and/or the relationship between addition and subtraction; CCSS 2.NBT.B.7: Add and subtract within 1000, using strategies and algorithms based on place value—focus here on within 100). When adding two-digit numbers, add ones first, then tens. If the ones sum is 10 or more, regroup: write the ones digit and carry 1 ten to the tens column (example: 47 + 28 → 7 + 8 = 15, write 5 and carry 1 → 4 + 2 + 1 = 7 → answer is 75). When subtracting, subtract ones first, then tens. If the ones digit in the top number is smaller than the ones digit in the bottom number, regroup (borrow): take 1 ten from the tens column and add 10 to the ones (example: 63 - 27 → can't do 3 - 7, so regroup 6 tens 3 ones into 5 tens 13 ones → 13 - 7 = 6, 5 - 2 = 3 → answer is 36). Place value strategy: Break numbers into tens and ones, add or subtract separately, combine (47 + 28 = 40 + 20 + 7 + 8 = 60 + 15 = 75). Number line: Start at first number, jump by tens then ones to add, or jump backward to subtract. In this problem, use the number line to add 34 + 27. To solve, on a number line start at 34, jump 20 to 54, then 7 to 61, or add ones: 4 + 7 = 11 (write 1, carry 1), tens: 3 + 2 + 1 = 6, answer 61. Choice C is correct because adding 34 + 27 using number line or algorithm—jump +20 to 54, +7 to 61, or with regrouping: 4 + 7 = 11 (write 1, carry 1), 3 + 2 + 1 = 6, giving 61. This correctly applies addition with regrouping. Choice A represents a basic fact error (perhaps 34 + 17 = 51 or misjumped on number line). This error typically happens when students make arithmetic mistakes, miscount jumps on the number line, or forget to carry. To help students: Teach regrouping explicitly with place value understanding. For addition: 'When ones add to 10 or more, we have too many ones. Group 10 ones into 1 ten. Write the remaining ones, carry the 1 ten.' Use base-ten blocks: 4 tens + 7 ones + 2 tens + 8 ones → combine ones (7 + 8 = 15 ones = 1 ten + 5 ones), combine tens (4 + 2 + 1 = 7 tens) → 75. For subtraction: 'If top ones < bottom ones, we need more ones. Borrow 1 ten (= 10 ones) from tens column.' Show with blocks: 6 tens 3 ones, need to subtract 7 ones (can't), so trade 1 ten for 10 ones (5 tens 13 ones), now can subtract. Practice standard algorithm vertically—align place values, work ones first then tens. Teach number line strategy: to add, jump forward; to subtract, jump backward. For word problems, identify operation: 'got more, combine, total' = add; 'gave away, left, how many more' = subtract. Practice mental math strategies: break apart by tens and ones, use friendly numbers. Watch for: not regrouping when needed, regrouping incorrectly (carrying/borrowing wrong amount), place value errors, wrong operation for context, basic arithmetic mistakes.