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Subtracting Within 100: Grade 2 Math Worksheet Answer Key – PDF Download

    This grade 2 subtract worksheet answer key solves all 22 problems of the subtracting within 100 worksheet step by step.

    Here are full worked answers for all 22 problems. Each answer shows the trade of a ten when one is needed. Each final answer is in bold. Read the steps with your child, and check each answer by adding back.

    Grade 2Common Core: 2.NBT.B.5 · 2.NBT.B.9

    Grade 2 Subtract Worksheet Answer Key: problems 1–5

    Problem 1: Subtract tens

    Subtract the tens. The ones stay the same.

    1. \(80 – 30 = 50\): 8 tens – 3 tens = 5 tens, and the ones stay 0. \(50\)
    2. \(95 – 40 = 55\): 9 tens – 4 tens = 5 tens, and the ones stay 5. \(55\)
    3. \(67 – 20 = 47\): 6 tens – 2 tens = 4 tens, and the ones stay 7. \(47\)
    4. \(74 – 50 = 24\): 7 tens – 5 tens = 2 tens, and the ones stay 4. \(24\)

    Problem 2: Blocks without trading

    The X marks 2 tens and 5 ones, which is 25. Count what is not crossed out: 2 tens and 3 ones. \(48 – 25 = 23\). \(23\) blocks

    Problem 3: Subtract ones

    Subtract the ones. The tens stay the same.

    1. \(56 – 3 = 53\): 6 – 3 = 3 ones, and the tens stay 5. \(53\)
    2. \(89 – 7 = 82\): 9 – 7 = 2 ones, and the tens stay 8. \(82\)
    3. \(74 – 4 = 70\): 4 – 4 = 0 ones, and the tens stay 7. \(70\)
    4. \(38 – 8 = 30\): 8 – 8 = 0 ones, and the tens stay 3. \(30\)

    Problem 4: No trade needed

    1. Ones: \(6 – 2 = 4\). Tens: \(8 – 5 = 3\). \(86 – 52 = 34\)
    2. Ones: \(7 – 5 = 2\). Tens: \(9 – 6 = 3\). \(97 – 65 = 32\)
    3. Ones: \(9 – 7 = 2\). Tens: \(3 – 1 = 2\). \(39 – 17 = 22\)
    4. Ones: \(4 – 3 = 1\). Tens: \(7 – 3 = 4\). \(74 – 33 = 41\)

    Problem 5: Trade a ten

    Trade 1 ten: 41 is 3 tens and 11 ones. Take away 1 ten and 8 ones. \(11 – 8 = 3\) ones and \(3 – 1 = 2\) tens.

    41 becomes 3 tens and 11 ones. Cross out 18: 1 ten and 8 ones. Left: 2 tens and 3 ones.

    \(41 – 18 = 23\)

    Grade 2 Subtract Worksheet Answer Key: problems 6–10

    Problem 6: Regroup the tens

    1. 4 tens is 40. \(40 + 12 = 52\). \(12\)
    2. 5 tens is 50. \(50 + 13 = 63\). \(13\)
    3. 7 tens is 70. \(70 + 10 = 80\). \(10\)
    4. 6 tens is 60. \(60 + 11 = 71\). \(6\)

    Problem 7: Column subtraction

    Ones: \(3\) is less than \(7\), so trade. The 6 tens becomes 5 tens, and the 3 ones becomes 13 ones. \(13 – 7 = 6\) and \(5 – 2 = 3\).

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    Trade 1 ten for 10 ones, then subtract.

    \(63 – 27 = 36\)

    Problem 8: Jumps back

    \(62 – 30 = 32\). Then \(32 – 5 = 27\). She jumped back 35 in all, because \(30 + 5 = 35\).

    20405070-30-5273262
    The jumps end at 27.

    She stops at \(27\). The problem is \(62 – 35 = 27\).

    Problem 9: Count up to subtract

    Add the jumps: \(3 + 20 + 1 = 24\). The gap from 67 to 91 is 24.

    \(91 – 67 = 24\)

    Problem 10: Trade then subtract

    1. Ones: \(3\) is less than \(6\), so trade 1 ten for 10 ones. Now there are \(13\) ones and \(7\) tens. Ones: \(13 – 6 = 7\). Tens: \(7 – 4 = 3\). \(83 – 46 = 37\)
    2. Ones: \(0\) is less than \(8\), so trade 1 ten for 10 ones. Now there are \(10\) ones and \(6\) tens. Ones: \(10 – 8 = 2\). Tens: \(6 – 3 = 3\). \(70 – 38 = 32\)
    3. Ones: \(5\) is less than \(9\), so trade 1 ten for 10 ones. Now there are \(15\) ones and \(4\) tens. Ones: \(15 – 9 = 6\). Tens: \(4 – 2 = 2\). \(55 – 29 = 26\)
    4. Ones: \(2\) is less than \(7\), so trade 1 ten for 10 ones. Now there are \(12\) ones and \(8\) tens. Ones: \(12 – 7 = 5\). Tens: \(8 – 5 = 3\). \(92 – 57 = 35\)

    Grade 2 Subtract Worksheet Answer Key: problems 11–15

    Problem 11: Zero in the ones

    1. Ones: \(0\) is less than \(7\), so trade 1 ten for 10 ones. Now there are \(10\) ones and \(5\) tens. Ones: \(10 – 7 = 3\). Tens: \(5 – 2 = 3\). \(60 – 27 = 33\)
    2. Ones: \(0\) is less than \(5\), so trade 1 ten for 10 ones. Now there are \(10\) ones and \(7\) tens. Ones: \(10 – 5 = 5\). Tens: \(7 – 4 = 3\). \(80 – 45 = 35\)
    3. Ones: \(0\) is less than \(8\), so trade 1 ten for 10 ones. Now there are \(10\) ones and \(8\) tens. Ones: \(10 – 8 = 2\). Tens: \(8 – 6 = 2\). \(90 – 68 = 22\)
    4. Ones: \(0\) is less than \(9\), so trade 1 ten for 10 ones. Now there are \(10\) ones and \(4\) tens. Ones: \(10 – 9 = 1\). Tens: \(4 – 1 = 3\). \(50 – 19 = 31\)

    Problem 12: Check with addition

    1. Ones: \(4\) is less than \(8\), so trade 1 ten for 10 ones. Now there are \(14\) ones and \(6\) tens. Ones: \(14 – 8 = 6\). Tens: \(6 – 3 = 3\). \(74 – 38 = 36\) Check: \(36 + 38 = 74\).
    2. Ones: \(1\) is less than \(5\), so trade 1 ten for 10 ones. Now there are \(11\) ones and \(8\) tens. Ones: \(11 – 5 = 6\). Tens: \(8 – 4 = 4\). \(91 – 45 = 46\) Check: \(46 + 45 = 91\).

    Problem 13: Find the mistake

    Leo took the smaller digit from the bigger digit in the ones column. But the top number is 52, so the ones are 2, not 7. He must trade 1 ten for 10 ones. Ones: \(2\) is less than \(7\), so trade 1 ten for 10 ones. Now there are \(12\) ones and \(4\) tens. Ones: \(12 – 7 = 5\). Tens: \(4 – 2 = 2\). \(52 – 27 = 25\)

    Check: \(25 + 27 = 52\).

    Problem 14: Missing part

    The whole is 85 and one part is 48. Ones: \(5\) is less than \(8\), so trade 1 ten for 10 ones. Now there are \(15\) ones and \(7\) tens. Ones: \(15 – 8 = 7\). Tens: \(7 – 4 = 3\). \(85 – 48 = 37\)

    85 stickers4837
    The missing part is 37.

    Check: \(37 + 48 = 85\).

    Problem 15: Missing number

    1. Add back: \(39 + 24 = 63\). \(63\)
    2. The missing number is the difference: \(82 – 47 = 35\). \(35\)
    3. Subtract: \(71 – 38 = 33\). \(33\)

    Grade 2 Subtract Worksheet Answer Key: problems 16–20

    Problem 16: Compare differences

    Ones: \(0\) is less than \(4\), so trade 1 ten for 10 ones. Now there are \(10\) ones and \(8\) tens. Ones: \(10 – 4 = 6\). Tens: \(8 – 3 = 5\). \(90 – 34 = 56\)

    Ones: \(0\) is less than \(9\), so trade 1 ten for 10 ones. Now there are \(10\) ones and \(7\) tens. Ones: \(10 – 9 = 1\). Tens: \(7 – 1 = 6\). \(80 – 19 = 61\)

    \(61 > 56\), so \(80 – 19\) is greater.

    Problem 17: Sticker swap

    Ones: \(4\) is less than \(8\), so trade 1 ten for 10 ones. Now there are \(14\) ones and \(5\) tens. Ones: \(14 – 8 = 6\). Tens: \(5 – 2 = 3\). \(64 – 28 = 36\)

    Check: \(36 + 28 = 64\). Maya has 36 stickers left.

    Problem 18: Library books

    Ones: \(1\) is less than \(7\), so trade 1 ten for 10 ones. Now there are \(11\) ones and \(8\) tens. Ones: \(11 – 7 = 4\). Tens: \(8 – 5 = 3\). \(91 – 57 = 34\)

    Check: \(34 + 57 = 91\). 34 books are left.

    Problem 19: Team points

    Find the gap between 75 and 49. Ones: \(5\) is less than \(9\), so trade 1 ten for 10 ones. Now there are \(15\) ones and \(6\) tens. Ones: \(15 – 9 = 6\). Tens: \(6 – 4 = 2\). \(75 – 49 = 26\)

    Check: \(26 + 49 = 75\). The Tigers scored 26 more points.

    Problem 20: Bake sale

    Step 1: \(100 – 47 = 53\). (Think of 100 as 9 tens and 10 ones. Ones: 10 – 7 = 3. Tens: 9 – 4 = 5.)

    Step 2: Ones: \(3\) is less than \(8\), so trade 1 ten for 10 ones. Now there are \(13\) ones and \(4\) tens. Ones: \(13 – 8 = 5\). Tens: \(4 – 3 = 1\). \(53 – 38 = 15\)

    Check: \(15 + 38 + 47 = 100\). 15 cookies are left.

    Grade 2 Subtract Worksheet Answer Key: problems 21–22

    Problem 21: Farmers market

    Step 1: Ones: \(6\) is less than \(9\), so trade 1 ten for 10 ones. Now there are \(16\) ones and \(7\) tens. Ones: \(16 – 9 = 7\). Tens: \(7 – 3 = 4\). \(86 – 39 = 47\)

    Step 2: Ones: \(7 – 5 = 2\). Tens: \(4 – 2 = 2\). \(47 – 25 = 22\)

    Check: \(22 + 25 + 39 = 86\). Diego has 22 apples left.

    Problem 22: Explain the strategy

    Jamal took away 40, but the problem says to take away only 38. He took away 2 too many. So he gives the 2 back: \(41 + 2 = 43\).

    Check with addition: \(43 + 38 = 81\). Yes, 43 is correct.

    How to use this grade 2 subtract worksheet answer key

    Read this grade 2 subtract worksheet answer key after trying each problem yourself, and redo any problem you missed.

    Next step after this grade 2 subtract worksheet answer key: Subtracting Within 100 test

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    Grade 2 Subtracting Within 100 worksheet answer key

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