1st Grade Math Quiz: Subtract Multiples Of 10
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Subtract Multiples Of 10Question 1 of 20

Use place value: 40-10=  

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30
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1st Grade Math Quiz

1st Grade Math Quiz: Subtract Multiples Of 10

Practice Subtract Multiples Of 10 in 1st Grade 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 Subtract Multiples Of 10, giving you a quick way to practice the rules, question types, and explanations that matter most for 1st Grade 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

Use place value: 40-10=  

  1. 20
  2. 30 (correct answer)
  3. 40
  4. 50
Explanation: When you see a subtraction problem like 40 - 10, place value is your best friend! Remember that numbers are built from tens and ones. The number 40 means 4 tens (and 0 ones), and 10 means 1 ten. Since both numbers have zero ones, you only need to think about the tens. Start with 4 tens and take away 1 ten. That leaves you with 3 tens: 4 tens - 1 ten = 3 tens. And 3 tens equals 30, which is the correct answer. Now let's see why the other choices don't work. The answer 20 would mean you took away 2 tens instead of 1 — that would be 40 - 20, not 40 - 10. The answer 40 means you didn't subtract anything at all; you kept all 4 tens, as if the problem were 40 - 0. The answer 50 is even bigger than 40, which can't be right because subtracting always makes a number smaller — that would be adding a ten, not taking one away. A great strategy to remember: when both numbers end in zero, just cover up the zeros and subtract the tens digits. Here, 4 - 1 = 3, then put the zero back to get 30. Also, keep this rule in mind — when you subtract, your answer should be smaller than the number you started with. That quick check helps you cross out answers like 40 and 50 right away!

Question 2

Subtract the tens: 90-70=  

  1. 10
  2. 20 (correct answer)
  3. 30
  4. 120
Explanation: When you subtract "tens," you can think of each ten as a group of 10, just like counting by tens: 10, 20, 30, and so on. The number 90 means 9 tens, and 70 means 7 tens. So the problem 90 - 70 is really asking: if you have 9 tens and take away 7 tens, how many tens are left? Start with 9 tens and remove 7 tens: 9 - 7 = 2. That leaves you with 2 tens, and 2 tens equals 20. So 90 - 70 = 20. Now look at why the other choices don't work. The answer 10 comes from subtracting only 8 tens instead of 7, or making a small counting slip — 9 - 7 is 2, not 1. The answer 30 is what you'd get if you subtracted just 6 tens (9 - 6 = 3), so you took away one group too few. The answer 120 is a trap because it comes from adding instead of subtracting: 90 + 30 or a mix-up of the tens — but the minus sign means you must take away, so your answer should be smaller than 90, never larger. A helpful tip: when both numbers end in 0, just cover up the zeros, subtract the front digits (9 - 7 = 2), then put the zero back to get 20. And always remember — subtraction makes numbers smaller, so any answer bigger than what you started with must be wrong.

Question 3

Subtract the tens: 40-30=  .

  1. 0
  2. 10 (correct answer)
  3. 20
  4. 70
Explanation: When you subtract numbers that are made of only tens, you can use a helpful trick: think about the tens as counting groups of ten. The number 40 means "4 tens," and 30 means "3 tens." So the problem 40 - 30 is really asking, "If I have 4 tens and take away 3 tens, how many tens are left?" Since 4 - 3 = 1, you have 1 ten left, and 1 ten equals 10. That's why 40 - 30 = 10. Let's look at why the other answers don't work. The answer 0 would only be right if you took away all the tens, like 40 - 40 — but here you're taking away just 3 tens, not 4. The answer 20 comes from subtracting too little, as if you only took away 2 tens (40 - 20 = 20) instead of 3. The answer 70 is what you'd get if you added the numbers (40 + 30 = 70) instead of subtracting — a common mix-up when you see two numbers together and grab the wrong operation. A great strategy for these problems: cover up the zeros and just subtract the front numbers. Here, cover the zeros to see 4 - 3 = 1, then put one zero back to get 10. Always double-check whether the sign tells you to take away (subtract) or put together (add) so you don't accidentally add when the problem wants you to subtract.

Question 4

Subtract tens from tens: 90-50= .

  1. 30
  2. 40 (correct answer)
  3. 50
  4. 140
Explanation: When you subtract tens from tens, there's a helpful shortcut: you can ignore the zeros for a moment and just subtract the "tens digits," then put the zero back at the end. Think of 90 as 9 tens and 50 as 5 tens. So the question really asks: how many tens are left when you take 5 tens away from 9 tens? Since 9 - 5 = 4, you have 4 tens left, which is 40. You can also count backward by tens: 90, 80, 70, 60, 50 — that's five jumps down, landing on 40. Now look at why the other choices don't work. The answer 30 comes from subtracting too much — it's what you'd get from 90 - 60, not 90 - 50. The answer 50 is a trap because it simply repeats one of the numbers in the problem; subtracting always makes the starting number smaller, so the answer can't stay at 50. The answer 140 is the result of adding the numbers (90 + 50 = 140) instead of subtracting — a common mix-up when you're moving fast. A smart strategy: whenever you see two "tens numbers" like 90 - 50, cover the zeros, do the tiny subtraction (9 - 5), then bring the zero back. And always remember — subtracting means the answer gets smaller, so any choice bigger than your starting number is definitely wrong.

Question 5

Count back by tens: start at 80, jump back 30. 80-30= .

  1. 40
  2. 50 (correct answer)
  3. 60
  4. 110
Explanation: Whenever you see "count back by tens," picture yourself hopping backward on a number line, landing on a smaller number with each jump. Since you're jumping back by tens, only the tens digit changes each hop, and the ones digit stays the same. Start at 80 and take three jumps of ten backward, because 30 is made of three tens: 80 → 70 → 60 → 50. After three jumps, you land on 50. You can also think of it as subtraction: 80 - 30 = 50, since 8 - 3 = 5 tens. Now look at why the other choices don't work. If you got 60, you only counted back two tens (80 → 70 → 60) and stopped one jump too early. If you got 40, you counted back four tens (80 → 70 → 60 → 50 → 40), taking one jump too many. The choice 110 is what happens if you add instead of subtract (80 + 30 = 110) — remember, jumping back means the number gets smaller, not bigger. A great trick for counting back by tens: just subtract the tens digits and keep the ones digit the same. Here, 8 tens minus 3 tens equals 5 tens, so the answer is 50. Whenever a problem says "jump back" or "count back," always check that your answer is smaller than where you started!

Question 6

Base-10 blocks show 7 tens. Remove 3 tens: 70-30= .

  1. 30
  2. 40 (correct answer)
  3. 50
  4. 100
Explanation: When you work with base-10 blocks, each "ten" block stands for a group of 10. So counting by tens is really just counting groups: 7 tens means 7 × 10 = 70. Subtracting tens works the same way — you just take away whole groups of ten and count what's left. Start with 7 tens. If you remove 3 tens, count how many ten-blocks remain: 7 - 3 = 4 tens. Since each ten is worth 10, that leaves you with 4 × 10 = 40. So 70 - 30 = 40. Now look at the other choices. The answer 30 is a trap because it's the 3 tens you removed, not the amount left behind — don't count what you took away. The answer 50 comes from subtracting only 2 tens instead of 3 (7 - 2 = 5), so it's a counting slip. The answer 100 is bigger than the number you started with, which can't happen when you subtract — removing blocks always makes the amount smaller, so this one should feel wrong right away. A helpful strategy: when subtracting tens, ignore the zeros for a moment and just subtract the "tens digits" (7 - 3 = 4), then put the zero back on to get 40. And always check direction — subtraction means the answer must be smaller than where you started, so eliminate any choice that's larger than 70 immediately.

Question 7

Chen counts back by tens: 30-10= .

  1. 10
  2. 20 (correct answer)
  3. 30
  4. 40
Explanation: When you "count back by tens," you start at a number and jump backward, taking away 10 each time. Think of it like hopping backward on a number line, but instead of small steps of 1, you take big steps of 10. A handy trick: when you subtract 10 from a two-digit number, the tens digit goes down by 1 and the ones digit stays the same. Start at 30. The tens digit is 3, so counting back one ten makes it 2, giving you 30 - 10 = 20. You can also picture it as 3 groups of ten, then removing 1 group, which leaves 2 groups of ten, or 20. Now look at why the other choices don't work. The answer 10 would be correct if you subtracted twice (30 - 10 - 10 = 10), but the question only asks you to count back one ten. The answer 30 is just the starting number — that happens if you forget to take anything away, or think 30 - 10 = 30. The answer 40 is bigger than 30, which is a sign you added a ten instead of subtracting; counting back always makes the number smaller. A good strategy to remember: when you count back, the number always gets smaller, so you can quickly cross out any choice that's the same as or bigger than where you started. Then just lower the tens digit by one for each ten you count back.

Question 8

Jamal has 70 crayons. He gives away 40. How many crayons left?

  1. 30 (correct answer)
  2. 110
  3. 40
  4. 70
Explanation: This question tests 1st grade subtraction of multiples of 10 in the range 10-90 (CCSS.1.NBT.6). When subtracting multiples of 10, use place value strategy: subtract tens from tens. Since both numbers end in 0 (have 0 ones), we only work with the tens place. The stimulus is a story where Jamal has 70 crayons and gives away 40. Choice A is correct because 7 tens - 4 tens = 3 tens = 30. Choice B is a common error where students add instead of subtract, getting 70 + 40 = 110, which happens because subtraction is more challenging than addition. To help students: Use base-10 blocks to physically remove ten-rods, counting what remains; practice on number lines with backward jumps of 10; emphasize 'subtract tens from tens' strategy; connect to skip counting backward by 10s; provide many examples showing pattern; use place value charts to organize tens; relate to real contexts like crayons in groups of 10.

Question 9

Sofia has 80 stickers. She gives away 50. How many left?

  1. 30 (correct answer)
  2. 130
  3. 50
  4. 20
Explanation: This question tests 1st grade subtraction of multiples of 10 in the range 10-90 (CCSS.1.NBT.6). When subtracting multiples of 10, use place value strategy: subtract tens from tens. Since both numbers end in 0 (have 0 ones), we only work with the tens place. The scenario is a story problem where Sofia has 80 stickers and gives away 50. Choice A is correct because 8 tens - 5 tens = 3 tens = 30. Choice B is a common error where students add instead of subtract, getting 80 + 50 = 130, which happens because subtraction is more challenging than addition. To help students: Use base-10 blocks to physically remove ten-rods, counting what remains; practice on number lines with backward jumps of 10; emphasize 'subtract tens from tens' strategy; connect to skip counting backward by 10s; provide many examples showing pattern; use place value charts to organize tens; connect to addition as inverse (80 - 50 = 30, check: 30 + 50 = 80); practice mental math with quick subtraction of tens; relate to real contexts like packages, dimes, groups of 10.

Question 10

Start at 80 on the number line and jump back 30. What number do you see?

  1. 40
  2. 60
  3. 50 (correct answer)
  4. 90
Explanation: This question tests 1st grade subtraction of multiples of 10 in the range 10-90 (CCSS.1.NBT.6). When subtracting multiples of 10, use place value strategy: subtract tens from tens. Since both numbers end in 0 (have 0 ones), we only work with the tens place; for example, 80 - 30 means 8 tens - 3 tens = 5 tens = 50. The stimulus shows a number line starting at 80 and jumping backward by 30. Choice C is correct because subtracting 30 from 80 means 8 tens - 3 tens = 5 tens = 50.

Question 11

Amir has 70 cents. He spends 20 cents. How much now?

  1. 90
  2. 50 (correct answer)
  3. 20
  4. 60
Explanation: This question tests 1st grade subtraction of multiples of 10 in the range 10-90 (CCSS.1.NBT.6). When subtracting multiples of 10, use place value strategy: subtract tens from tens. Since both numbers end in 0 (have 0 ones), we only work with the tens place. The scenario is a story where Amir has 70 cents and spends 20 cents. Choice B is correct because 7 tens - 2 tens = 5 tens = 50. Choice A is a common error where students add instead of subtract, getting 70 + 20 = 90, which happens because subtraction is more challenging than addition. To help students: Use base-10 blocks to physically remove ten-rods, counting what remains; practice on number lines with backward jumps of 10; emphasize 'subtract tens from tens' strategy; connect to skip counting backward by 10s; provide many examples showing pattern; use place value charts to organize tens; connect to addition as inverse (70 - 20 = 50, check: 50 + 20 = 70); practice mental math with quick subtraction of tens; relate to real contexts like packages, dimes, groups of 10.

Question 12

Subtract tens from tens: 60-20=  

  1. 20
  2. 30
  3. 40 (correct answer)
  4. 50
Explanation: When you subtract tens from tens, you can use a helpful trick: just look at the tens digits and subtract those, then add the zero back at the end. Think of the numbers as groups of ten. 60 means 6 tens, and 20 means 2 tens. So the question is really asking: how many tens are left when you take 2 tens away from 6 tens? That's 6 - 2 = 4, which gives you 4 tens, or 40. You can picture it as counting bundles: start with 6 bundles of ten and remove 2 bundles — you're left with 4 bundles, and 4 bundles of ten make 40. Now let's check why the other choices don't work. The answer 50 comes from subtracting only 1 ten instead of 2 (6 - 1 = 5) — you didn't take away enough. The answer 30 comes from subtracting 3 tens (6 - 3 = 3) — you took away too much. The answer 20 is a trap because it just repeats the number you were subtracting; subtracting is not the same as copying one of the numbers. A good strategy for these "tens minus tens" problems is to cover up the zeros, subtract the small numbers you see, then put the zero back. For 60 - 20: cover the zeros to get 6 - 2 = 4, then add the zero to make 40. Practice this trick and these problems become quick and easy!

Question 13

Sofia has 60 stickers in tens. She gives away 20. How many left?

  1. 60
  2. 40 (correct answer)
  3. 80
  4. 30
Explanation: This question tests 1st grade subtraction of multiples of 10 in the range 10-90 (CCSS.1.NBT.6). When subtracting multiples of 10, use place value strategy: subtract tens from tens. Since both numbers end in 0 (have 0 ones), we only work with the tens place. The stimulus is a story where Sofia has 60 stickers in tens and gives away 20. Choice B is correct because 6 tens−2 tens=4 tens=406 \text{ tens} - 2 \text{ tens} = 4 \text{ tens} = 40. Choice A is a common error where students use one of the original numbers instead of finding the difference, picking 60, which happens because keeping track of place value during subtraction requires practice. To help students: Use base-10 blocks to physically remove ten-rods, counting what remains; practice on number lines with backward jumps of 10; emphasize 'subtract tens from tens' strategy; connect to skip counting backward by 10s; provide many examples showing pattern; use place value charts to organize tens; relate to real contexts like stickers in groups of 10.

Question 14

Place value: 6 tens minus 2 tens. 60-20= .

  1. 30
  2. 40 (correct answer)
  3. 50
  4. 80
Explanation: When you see a subtraction problem with tens, like 60 - 20, the trick is to think about it in groups of ten instead of counting one by one. The word "tens" is your clue: you're not subtracting single things, you're taking away whole groups of ten. Start by counting the tens. The number 60 is made of 6 tens, and 20 is made of 2 tens. When you subtract, you just take 2 tens away from 6 tens: 6 - 2 = 4 tens. And 4 tens equals 40, so 60 - 20 = 40. Now look at the other choices. The answer 30 comes from subtracting one too many tens, as if you did 6 - 3 instead of 6 - 2. The answer 50 comes from subtracting only 1 ten (6 - 1) instead of 2 tens, so you didn't take away enough. The answer 80 is a trap because it comes from adding the tens (6 + 2 = 8 tens) instead of subtracting — always check whether the problem says take away or put together. A helpful strategy: when a problem uses only tens with zeros at the end, cover up the zeros and solve the simple fact first. Here you'd cover the zeros to get 6 - 2 = 4, then bring the zero back to make 40. This "cover the zeros" trick keeps you from miscounting and works every time with tens.

Question 15

Maya has 50 crayons. She uses 50. How many crayons does Maya have left?

  1. 50
  2. 10
  3. 0 (correct answer)
  4. 100
Explanation: Maya starts with 50 crayons and uses all 50, so she has 0 left. 50 would mean she didn't use any crayons at all. 10 doesn't match either the starting amount or the amount used. 100 is more crayons than Maya even started with. Since she used exactly as many as she had, 0 crayons are left.

Question 16

What is 80−3080-30?

  1. 40
  2. 110
  3. 50 (correct answer)
  4. 80
Explanation: 80 minus 30 equals 50. 40 subtracts 40 instead of 30. 110 adds the two numbers together instead of subtracting. 80 repeats the starting number without subtracting anything. Only 50 correctly shows the difference between 80 and 30.

Question 17

Subtract tens from tens: 30-20= .

  1. 0
  2. 10 (correct answer)
  3. 20
  4. 50
Explanation: When you subtract tens from tens, a neat trick makes it easy: you can ignore the zeros for a moment and just subtract the "tens" numbers. Think of 30 as 3 tens and 20 as 2 tens. Taking away 2 tens from 3 tens leaves 1 ten, and 1 ten is written as 10. You can also picture it with objects: imagine 3 bundles of ten sticks. If you give away 2 bundles, you have 1 bundle left — that's 10 sticks. So 30 - 20 = 10, which is the correct answer. Now let's see why the other choices don't work. The answer 0 would only be true if you took away all the tens, like 30 - 30 — but here you only remove 2 tens, not 3. The answer 20 is a trap because it just copies the second number in the problem instead of actually subtracting; subtraction means finding what's left over, not repeating a number. The answer 50 is what you'd get if you added the numbers (30 + 20), but the minus sign tells you to take away, not combine. A helpful strategy: whenever you subtract round tens, cover the zeros with your finger, subtract the small numbers (3 - 2 = 1), then put one zero back on the end. Always double-check the sign too — a minus sign means "take away and find how much is left," while a plus sign means "put together."

Question 18

Subtract tens from tens: 60-20= . What is the difference?

  1. 30
  2. 40 (correct answer)
  3. 50
  4. 80
Explanation: When you subtract tens from tens, the trick is to think of each number in groups of ten and just subtract the "how many tens" part. Think of 60 as 6 tens and 20 as 2 tens. If you have 6 groups of ten and take away 2 groups of ten, you're left with 4 groups of ten. So 6 tens - 2 tens = 4 tens, and 4 tens is 40. That's why the difference is 60 - 20 = 40. Now let's look at why the other answers don't work. The answer 30 comes from subtracting one too many tens — like doing 60 - 30 instead of 60 - 20. The answer 50 is the opposite mistake: taking away only 1 ten (60 - 10) instead of 2 tens. The answer 80 is a big warning sign — that's what you'd get if you added the tens (60 + 20) instead of subtracting them, so watch the minus sign carefully! A helpful strategy: whenever both numbers end in zero, cover up the zeros in your mind and just subtract the front digits. Here, 6 - 2 = 4, then put the zero back to get 40. This "hide the zero" shortcut makes tens-subtraction quick and keeps you from miscounting.

Question 19

The base-10 blocks show 70−3070-30. What is the difference?

  1. 100
  2. 40 (correct answer)
  3. 30
  4. 4
Explanation: This question tests 1st grade subtraction of multiples of 10 in the range 10-90 (CCSS.1.NBT.6). When subtracting multiples of 10, use place value strategy: subtract tens from tens. Since both numbers end in 0 (have 0 ones), we only work with the tens place. The stimulus shows base-10 blocks representing 70-30, likely with 7 ten-rods minus 3 ten-rods. Choice B is correct because 7 tens - 3 tens = 4 tens = 40. Choice A is a common error where students add instead of subtract, getting 70 + 30 = 100, which happens because subtraction is more challenging than addition. To help students: Use base-10 blocks to physically remove ten-rods, counting what remains; practice on number lines with backward jumps of 10; emphasize 'subtract tens from tens' strategy; connect to skip counting backward by 10s; provide many examples showing pattern; use place value charts to organize tens; connect to addition as inverse (70 - 30 = 40, check: 40 + 30 = 70); practice mental math with quick subtraction of tens; relate to real contexts like packages, dimes, groups of 10.

Question 20

Amir has 80 blocks in tens. He takes away 10. How many left?

  1. 90
  2. 60
  3. 70 (correct answer)
  4. 80
Explanation: This question tests 1st grade subtraction of multiples of 10 in the range 10-90 (CCSS.1.NBT.6). When subtracting multiples of 10, use place value strategy: subtract tens from tens. Since both numbers end in 0 (have 0 ones), we only work with the tens place. The stimulus is a story where Amir has 80 blocks in tens and takes away 10. Choice C is correct because 8 tens - 1 ten = 7 tens = 70. Choice A is a common error where students add instead of subtract, getting 80 + 10 = 90, which happens because subtraction is more challenging than addition. To help students: Use base-10 blocks to physically remove ten-rods, counting what remains; practice on number lines with backward jumps of 10; emphasize 'subtract tens from tens' strategy; connect to skip counting backward by 10s; provide many examples showing pattern; use place value charts to organize tens; relate to real contexts like blocks in groups of 10.