Elementary School Math Quiz: Multiply By Multiples Of 10
20 questions · exam conditions
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Multiply By Multiples Of 10Question 1 of 20

A school cafeteria serves lunch to students in groups. If 7 groups of 40 students each eat lunch, and then 3 more groups of 40 students each eat lunch, what is the total number of students who ate lunch?

280280 students total
400400 students total
320320 students total
120120 students total
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Elementary School Math Quiz

Elementary School Math Quiz: Multiply By Multiples Of 10

Practice Multiply By Multiples Of 10 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 Multiply By Multiples Of 10, 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

A school cafeteria serves lunch to students in groups. If 7 groups of 40 students each eat lunch, and then 3 more groups of 40 students each eat lunch, what is the total number of students who ate lunch?

  1. 280280 students total
  2. 400400 students total (correct answer)
  3. 320320 students total
  4. 120120 students total
Explanation: First group: 7×40=2807 \times 40 = 280 students. Second group: 3×40=1203 \times 40 = 120 students. Total: 280+120=400280 + 120 = 400 students. Choice A shows only the first group, choice C shows 8×408 \times 40, and choice D shows only the second group.

Question 2

What is 7×307 \times 30?

  1. 21
  2. 210 (correct answer)
  3. 70
  4. 37
Explanation: Multiplying 7 by 30 gives 210, since 7×3=217 \times 3 = 21 and then multiplying by 10 gives 210. Choice A (21) is the result of 7×37 \times 3 without accounting for the extra ten. Choice C (70) mixes up the factors, treating it like 7×107 \times 10. Choice D (37) comes from adding 7 and 30 instead of multiplying.

Question 3

If 4×3=124 \times 3 = 12, what is 4×3004 \times 300?

  1. 12000
  2. 120
  3. 1200 (correct answer)
  4. 12
Explanation: 1200 is correct because 4×300=12004 \times 300 = 1200. 12000 is incorrect; it has an extra zero, ten times too many. 120 is incorrect because it's the result of 4×304 \times 30, one zero short of the correct product. 12 is incorrect; it's just the given fact restated, without scaling up by 100.

Question 4

A coach gives 6 players 40 points each. How many points total?

  1. 24 points
  2. 240 points (correct answer)
  3. 60 points
  4. 46 points
Explanation: Multiplying 6 players by 40 points each gives 6 times 40, which is 240 points total. Choice A, 24 points, comes from multiplying 6 by 4 and dropping a zero. Choice C, 60 points, is not the product of 6 and 40. Choice D, 46 points, comes from adding 6 and 40 instead of multiplying.

Question 5

Leo has 4 boxes with 90 crayons in each box. How many crayons does he have in total?

  1. 360 crayons (correct answer)
  2. 900 crayons
  3. 36 crayons
  4. 94 crayons
Explanation: Leo has 4 boxes with 90 crayons each, so the total is 4 times 90, which is 360 crayons. Choice B (900 crayons) comes from multiplying with an extra zero in the wrong place. Choice C (36 crayons) drops a zero from the correct total by mistake. Choice D (94 crayons) comes from adding 4 and 90 instead of multiplying.

Question 6

What is 4×704 \times 70?

  1. 28
  2. 2800
  3. 280 (correct answer)
  4. 74
Explanation: 280 is correct because 4×70=2804 \times 70 = 280. 28 is incorrect; it's the product of 4 and 7 without accounting for the extra zero in 70. 2800 is incorrect because it has one too many zeros. 74 is incorrect; it doesn't represent multiplying 4 by 70.

Question 7

Use the pattern: If 4×5=204\times5=20, what is 4×504\times50?

  1. 20
  2. 200 (correct answer)
  3. 40
  4. 2000
Explanation: Since 50 is 10 times 5, the product 4 times 50 is 10 times the product of 4 times 5, so 4 times 50 equals 200. Choice A, 20, repeats the original fact without scaling it up. Choice C, 40, only doubles the original product instead of multiplying it by 10. Choice D, 2000, scales the product by 100 instead of 10.

Question 8

Ava has 7 bags with 10 marbles in each bag. How many marbles does she have in total?

  1. 17 marbles
  2. 7 marbles
  3. 700 marbles
  4. 70 marbles (correct answer)
Explanation: 70 marbles is correct because 7×10=707 \times 10 = 70. 17 marbles is incorrect; it comes from adding 7 and 10 instead of multiplying. 7 marbles is incorrect because it's just the number of bags, not the total marbles. 700 marbles is incorrect; it has an extra zero, far more than the actual product.

Question 9

A coach gives 6 players 40 points each. How many points total?

  1. 46 points
  2. 60 points
  3. 24 points
  4. 240 points (correct answer)
Explanation: This question tests multiplying one-digit numbers by multiples of 10 in the range 10-90 (CCSS.3.NBT.3), specifically using place value strategies and properties of operations. To multiply a digit by a multiple of 10, use the pattern: first multiply the digit by the unit digit, then multiply the result by 10. For example, 6×40: Think of 40 as 4 tens. Multiply 6×4=24, then multiply by 10 to get 240 (or think: 24 tens = 240). In this problem, a coach gives 6 players 40 points each. This represents the multiplication 6×40. Choice A is correct because 6×40=240 using the pattern (6×4=24, then ×10=240) or place value (6×4 tens = 24 tens = 240). This demonstrates understanding of multiplying by multiples of 10. Choice C is incorrect because it shows only 6×4=24 and forgot to multiply by 10. This error occurs when students don't complete the pattern. To help students multiply by multiples of 10: Connect to basic facts (if you know 6×4=24, then 6×40=240). Use place value language (6×40 = 6×4 tens = 24 tens = 240). Model with base-10 blocks (6 groups of 4 tens rods).

Question 10

Mia buys 6 packs of 30 stickers. How many stickers total?

  1. 60 stickers
  2. 1800 stickers
  3. 180 stickers (correct answer)
  4. 18 stickers
Explanation: 180 stickers is correct because 6 times 30 equals 180. 60 stickers is incorrect because it does not match multiplying 6 by 30. 1800 stickers is incorrect because it adds an extra zero, mistaking the place value. 18 stickers is incorrect because it comes from 6 times 3, ignoring the correct place value.

Question 11

Lena has 6 packs of 30 stickers. How many stickers does she have in total?

  1. 60 stickers
  2. 180 stickers (correct answer)
  3. 1800 stickers
  4. 18 stickers
Explanation: 6 packs of 30 stickers gives 6 times 30, which equals 180 stickers, so B is correct. Choice A (60) uses only part of the packs. Choice C (1800) adds an extra zero to the correct product. Choice D (18) confuses the number of packs with the total number of stickers.

Question 12

What is 8×408 \times 40?

  1. 320 (correct answer)
  2. 80
  3. 3200
  4. 48
Explanation: 320 is correct because 8 times 40 equals 320. 80 is incorrect because it uses only one of the factors. 3200 is incorrect because it adds an extra zero, mistaking the place value. 48 is incorrect because it comes from adding 8 and 40 instead of multiplying them.

Question 13

Kai has 6 groups of 20 marbles. How many marbles in all?

  1. 12 marbles
  2. 60 marbles
  3. 120 marbles (correct answer)
  4. 26 marbles
Explanation: Multiplying 6 groups by 20 marbles each gives 6 times 20, which is 120 marbles. Choice A, 12 marbles, comes from multiplying 6 by 2 and dropping a zero. Choice B, 60 marbles, comes from multiplying 6 by 10 instead of 20. Choice D, 26 marbles, comes from adding 6 and 20 instead of multiplying.

Question 14

Use skip counting by 20s six times to find 6×206 \times 20.

  1. 12
  2. 60
  3. 120 (correct answer)
  4. 26
Explanation: Skip counting by 20 six times gives 20, 40, 60, 80, 100, 120, so 6 x 20 = 120, making Choice C correct. Choice A (12) drops a zero from the correct product. Choice B (60) stops after only three skips instead of six. Choice D (26) comes from adding 6 + 20 instead of multiplying.

Question 15

What is 6×306\times 30?

  1. 1800
  2. 18
  3. 180 (correct answer)
  4. 60
Explanation: 6 x 30 equals 180, since 6 x 3 = 18 and 30 has one extra zero, so the product also gets one extra zero. Choice A (1800) adds two extra zeros instead of one. Choice B (18) is the value of 6 x 3, not 6 x 30. Choice D (60) mistakenly multiplies 6 by 10 instead of 30.

Question 16

Mia buys 6 packs of 30 stickers. How many stickers total?

  1. 60 stickers
  2. 180 stickers (correct answer)
  3. 1800 stickers
  4. 18 stickers
Explanation: 6 packs of 30 stickers is 6 x 30 = 180 stickers, making Choice B correct. Choice C (1800) adds an extra zero to the correct product. Choice A (60) and Choice D (18) both come from using the wrong number of packs or stickers per pack.

Question 17

At a library, each bookshelf holds 80 books. The library has 4 bookshelves that are completely full and 3 bookshelves that are completely empty. How many books are on the shelves in total?

  1. 560560 books total
  2. 240240 books total
  3. 320320 books total (correct answer)
  4. 8080 books total
Explanation: Only the full shelves contain books. Books on full shelves: 4×80=3204 \times 80 = 320 books. Empty shelves contribute 0 books. Total books: 320+0=320320 + 0 = 320 books. Choice A shows 7×807 \times 80, choice B shows 3×803 \times 80, and choice D shows just one shelf.

Question 18

Refer to the table showing prices at a snack shop. Mia buys 4 bags of pretzels and 3 bags of chips. How much does she spend in cents?

  1. 390390 cents (correct answer)
  2. 350350 cents
  3. 490490 cents
  4. 210210 cents
Explanation: Pretzels: 4×60=2404 \times 60 = 240 cents. Chips: 3×50=1503 \times 50 = 150 cents. Total: 240+150=390240 + 150 = 390 cents. Choice B multiplies wrong (4×504\times50). Choice C swaps prices. Choice D adds the multipliers incorrectly.

Question 19

Marcus says 5×60=3005 \times 60 = 300 because 5×6=305 \times 6 = 30 and then he puts a zero at the end. Using the same strategy, what is 9×709 \times 70?

  1. 630630 (correct answer)
  2. 540540
  3. 6363
  4. 6,3006{,}300
Explanation: When you multiply a one-digit number by a multiple of 10, you can use a helpful shortcut: multiply the non-zero digits together, then attach the zero from the tens number to the end of your answer. This works because multiplying by 60 is the same as multiplying by 6 and then by 10. For 9×709 \times 70, start with the basic fact: 9×7=639 \times 7 = 63. Then attach the zero from the 70 to get 630630. So the answer is A. Choice B (540540) comes from a multiplication error — mixing up 9×6=549 \times 6 = 54 instead of using 9×79 \times 7. Be careful to use the correct digits from the original problem. Choice C (6363) is what you get if you forget the most important step: attaching the zero at the end. Since you're multiplying by 70 (not 7), your answer needs to be ten times bigger. Choice D (6,3006{,}300) adds two zeros instead of one. You only add one zero because 70 has only one zero — not two. A good tip to remember: count the zeros in the numbers you're multiplying, then attach that same number of zeros to your basic multiplication fact. Since 7070 has one zero, your answer gets one zero at the end. This "count the zeros" trick will help you quickly solve problems like 8×908 \times 90 or 4×5004 \times 500 without having to write out the full multiplication.

Question 20

Which product is GREATER than 5×805 \times 80?

  1. 7×607 \times 60 (correct answer)
  2. 4×904 \times 90
  3. 6×606 \times 60
  4. 8×408 \times 40
Explanation: When you're comparing products without a calculator, the fastest strategy is to compute the target value first, then check each option against it. Here, 5×80=4005 \times 80 = 400, so you're looking for a product greater than 400. Now test each choice: Option A: 7×60=4207 \times 60 = 420. That's greater than 400. ✓ Option B: 4×90=3604 \times 90 = 360. Less than 400. Option C: 6×60=3606 \times 60 = 360. Less than 400. Option D: 8×40=3208 \times 40 = 320. Less than 400. Only A produces a product larger than 5×805 \times 80, making it the correct choice. Notice a helpful pattern here: just because a product has "bigger looking" numbers doesn't mean the result is bigger. For example, D has an 8 (larger than the 5 in the original), but because the other factor dropped from 80 to 40, the total shrank. Multiplication depends on both factors working together, not just one being large. Study tip: When comparing multiplication expressions, always calculate the target value first and write it down. Then work through each option in order. Also, remember that multiplying by a multiple of 10 is quick — just multiply the non-zero digits and add the zero back on (for example, 7×6=427 \times 6 = 42, so 7×60=4207 \times 60 = 420). This shortcut will save you time on many 3rd-grade multiplication problems.