Subtraction Within 100

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Subtraction Within 100 · Grade 2 · Worksheet 3

1. Olivia had 49 toy cars. Olivia lost 24 of them at the park. How many toy cars does Olivia still have? Answer: 25 Solution: Olivia started with 49 toy cars. Subtract the 24 cars that were lost: 49 - 24 = 25. Olivia still has 25 toy cars.
   Full step-by-step solution

   Step 1: Olivia started with 49 toy cars. Step 2: Subtract the 24 cars that were lost: 49 - 24 = 25. Olivia still has 25 toy cars.

2. Tane has a strip of paper that is 73 centimeters long. He cuts off a piece that is 45 centimeters long. How long is the remaining piece of paper? Answer: 28 Solution: The whole strip is 73 centimeters long. The cut piece is 45 centimeters long. To find the remaining piece, subtract the cut piece from the whole: 73 - 45.
   Full step-by-step solution

   Step 1: The whole strip is 73 centimeters long. Step 2: The cut piece is 45 centimeters long. Step 3: To find the remaining piece, subtract the cut piece from the whole: 73 - 45. Step 4: Subtract the ones: 3 - 5. Since 3 is less than 5, borrow 1 ten from the tens place. 73 becomes 60 + 13. Now 13 - 5 = 8. Step 5: Subtract the tens: 6 - 4 = 2. Step 6: The remaining piece is 28 centimeters long. The answer is 28.

3. Liam collected 85 seashells at the beach. He gave 27 of them to his friend Noah. How many seashells does Liam have left? Answer: 58 Solution: Liam started with 85 seashells. He gave away 27 seashells, so we need to subtract: 85 - 27 Subtract the ones place: 5 - 7, which we can't do, so we regroup from the tens place. 85 becomes 70 + 15.
   Full step-by-step solution

   Step 1: Liam started with 85 seashells. Step 2: He gave away 27 seashells, so we need to subtract: 85 - 27 Step 3: Subtract the ones place: 5 - 7, which we can't do, so we regroup from the tens place. 85 becomes 70 + 15. Step 4: Now subtract ones: 15 - 7 = 8 Step 5: Subtract tens: 70 - 20 = 50 Step 6: Combine the results: 50 + 8 = 58 Liam has 58 seashells left.

4. 72 - 38 = ? Answer: 34 Solution: 72 - 38 Start subtracting from the rightmost column (ones place). In 72, the ones digit is 2. In 38, the ones digit is 8.
   Full step-by-step solution

   Let's solve 72 - 38 step by step. Step 1: Write the problem vertically in your mind: 72 - 38 Step 2: Start subtracting from the rightmost column (ones place). In 72, the ones digit is 2. In 38, the ones digit is 8. Since 2 is smaller than 8, we cannot subtract directly. Step 3: We need to borrow from the tens place. The 7 in the tens place of 72 means 7 tens, which is 70. Take 1 ten from the 7 tens, leaving 6 tens. That 1 ten equals 10 ones. Add these 10 ones to the existing 2 ones: 10 + 2 = 12 ones. Step 4: Now subtract the ones column: 12 ones - 8 ones = 4 ones. Write down 4 in the ones place of the answer. Step 5: Move to the tens column. After borrowing, the tens digit of 72 is now 6 (not 7). Subtract the tens: 6 tens - 3 tens = 3 tens. Write down 3 in the tens place of the answer. Step 6: Combine the digits: 3 tens and 4 ones gives 34. Therefore, 72 - 38 = 34.

5. Liam had 85 stickers in his collection. He gave 27 stickers to his friend Noah during recess. How many stickers does Liam have left? Answer: 58 Solution: Liam started with 85 stickers He gave away 27 stickers Subtract the stickers he gave away from what he started with: 85 - 27 First subtract the ones: 5 - 7, we can't do this so we borrow 1 ten from the tens place 85 becomes 7 tens and 15 ones 15 ones - 7 ones = 8 ones 7 tens - 2 tens = 5 tens…
   Full step-by-step solution

   Step 1: Liam started with 85 stickers Step 2: He gave away 27 stickers Step 3: Subtract the stickers he gave away from what he started with: 85 - 27 Step 4: First subtract the ones: 5 - 7, we can't do this so we borrow 1 ten from the tens place Step 5: 85 becomes 7 tens and 15 ones Step 6: 15 ones - 7 ones = 8 ones Step 7: 7 tens - 2 tens = 5 tens Step 8: Combine the tens and ones: 5 tens and 8 ones = 58 Step 9: Liam has 58 stickers left

6. 84 - 39 = ? Answer: 45 Solution: 84 -39 Look at the ones place: 4 - 9. Since 4 is smaller than 9, we need to regroup. Take 1 ten from the 8 tens, leaving 7 tens.
   Full step-by-step solution

   Step 1: Write the problem vertically: 84 -39 --- Step 2: Look at the ones place: 4 - 9. Since 4 is smaller than 9, we need to regroup. Step 3: Take 1 ten from the 8 tens, leaving 7 tens. Add 10 ones to the 4 ones, making 14 ones. Step 4: Now subtract in the ones place: 14 - 9 = 5 Step 5: Subtract in the tens place: 7 - 3 = 4 Step 6: Combine the results: 4 tens and 5 ones = 45 The answer is 45.

7. Matiu had 78 stickers. Matiu gave 1 stickers to a friend. How many stickers does Matiu have now? Answer: 77 Solution: Start with 78 stickers. Subtract the 1 stickers given away: 78 - 1 = 77.
   Full step-by-step solution

   Step 1: Start with 78 stickers. Step 2: Subtract the 1 stickers given away: 78 - 1 = 77. The answer is 77 stickers.

8. Kai picked 99 flowers from the garden. Then Kai gave 42 flowers to mom. How many flowers does Kai have left? Answer: 57 Solution: Kai picked 99 flowers. Kai gave away 42 flowers, so subtract: 99 - 42 = 57. Kai has 57 flowers left.
   Full step-by-step solution

   Step 1: Kai picked 99 flowers. Step 2: Kai gave away 42 flowers, so subtract: 99 - 42 = 57. Kai has 57 flowers left.

9. 92 - 57 = ? Answer: 35 Solution: 92 -57 Look at the ones place: 2 - 7. Since 2 is smaller than 7, we need to regroup. Take 1 ten from the 9 tens, leaving 8 tens.
   Full step-by-step solution

   Step 1: Write the problem vertically: 92 -57 --- Step 2: Look at the ones place: 2 - 7. Since 2 is smaller than 7, we need to regroup. Step 3: Take 1 ten from the 9 tens, leaving 8 tens. Add 10 ones to the 2 ones, making 12 ones. Step 4: Now subtract in the ones place: 12 - 7 = 5 Step 5: Subtract in the tens place: 8 - 5 = 3 Step 6: Combine the results: 35 The answer is 35.

10. 45 - 18 = ? Answer: 27 Solution: Write the problem vertically in your mind, aligning the digits by place value (ones and tens). 45 - 18 Start by subtracting the numbers in the ones column (rightmost column). We have 5 - 8.
    Full step-by-step solution

    Let's solve 45 - 18 step-by-step. Step 1: Write the problem vertically in your mind, aligning the digits by place value (ones and tens). 45 - 18 Step 2: Start by subtracting the numbers in the ones column (rightmost column). We have 5 - 8. Since 5 is smaller than 8, we cannot subtract directly. We need to borrow from the tens column. Step 3: Borrow 1 ten from the 4 in the tens column. 1 ten is the same as 10 ones. So, the 4 in the tens place becomes 3 (because we borrowed 1), and the 5 in the ones place becomes 15 (5 + 10). So now we have: Tens column: 3 (after borrowing) Ones column: 15 Step 4: Now subtract the ones column: 15 - 8 = 7. Write down 7 in the ones place of the answer. Step 5: Now subtract the tens column: 3 - 1 = 2. Write down 2 in the tens place of the answer. Step 6: Combine the digits from the tens and ones columns: 2 and 7 gives 27. So, 45 - 18 = 27.