Multi-Digit Operations

lessonbunny.com

Answer Key & Explanations

Multi-Digit Operations · Grade 4 · Worksheet 1

1. Liam is collecting baseball cards. He has 128 cards in his main collection and his friend Noah gives him 57 more cards. Then Liam decides to give 34 cards to his younger sister. How many baseball cards does Liam have now? Answer: 151 Solution: 1. Liam starts with 128 baseball cards. So, initial amount = 128.
   Full step-by-step solution

   Let's go step by step. 1. Liam starts with 128 baseball cards. So, initial amount = 128. 2. Noah gives him 57 more cards. This means we add 57 to 128. 128 + 57 = 185. Now Liam has 185 cards. 3. Liam gives 34 cards to his younger sister. This means we subtract 34 from 185. 185 − 34 = 151. 4. So, Liam now has 151 baseball cards. Final answer: 151

2. At the school book fair, Kai bought 3338 books. Later, Kai's friend gave Kai 3283 more books. How many books does Kai have in total? Answer: 6621 Solution: Start with 3338 books. Add 3283 more books: 3338 + 3283 = 6621. Kai has 6621 books in total.
   Full step-by-step solution

   Step 1: Start with 3338 books. Step 2: Add 3283 more books: 3338 + 3283 = 6621. Kai has 6621 books in total.

3. 45,321 + 23,678 = ? Answer: 68,999 Solution: Write the numbers vertically, aligning by place value: 45,321 + 23,678 Add the ones column: 1 + 8 = 9. Write 9. Add the tens column: 2 + 7 = 9.
   Full step-by-step solution

   Step 1: Write the numbers vertically, aligning by place value: 45,321 + 23,678 -------- Step 2: Add the ones column: 1 + 8 = 9. Write 9. Step 3: Add the tens column: 2 + 7 = 9. Write 9. Step 4: Add the hundreds column: 3 + 6 = 9. Write 9. Step 5: Add the thousands column: 5 + 3 = 8. Write 8. Step 6: Add the ten-thousands column: 4 + 2 = 6. Write 6. Step 7: Combine the results: 68,999. The answer is 68,999.

4. Liam is organizing his baseball card collection. He has 347 cards in his main album and his friend Noah gives him 128 more cards. How many baseball cards does Liam have in total now? Answer: 475 Solution: Liam starts with 347 cards in his main album. Noah gives him 128 more cards. So we need to calculate: 347 + 128.
   Full step-by-step solution

   Let's add the number of baseball cards Liam has step by step. Step 1: Liam starts with 347 cards in his main album. Step 2: Noah gives him 128 more cards. So we need to calculate: 347 + 128. Step 3: Add the ones place digits: 7 (from 347) + 8 (from 128) = 15. Write down 5 in the ones place, and carry over 1 to the tens place. Step 4: Add the tens place digits: 4 (from 347) + 2 (from 128) = 6, plus the carried over 1 makes 7. Write down 7 in the tens place. Step 5: Add the hundreds place digits: 3 (from 347) + 1 (from 128) = 4. Write down 4 in the hundreds place. Step 6: Combine the digits: 4 hundreds, 7 tens, 5 ones = 475. So, Liam now has 475 baseball cards in total.

5. Emma is organizing a school fundraiser. She collected 347 cookies from students and bought 128 more from the store. If she packages them into boxes of 25 cookies each, how many complete boxes can she make? Answer: 19 Solution: 347 cookies collected + 128 cookies bought = 475 cookies total Divide the total cookies by the number that fits in each box 475 ÷ 25 = ?
   Full step-by-step solution

   Step 1: Find the total number of cookies Emma has 347 cookies collected + 128 cookies bought = 475 cookies total Step 2: Divide the total cookies by the number that fits in each box 475 ÷ 25 = ? Step 3: Calculate the division 25 × 19 = 475 475 ÷ 25 = 19 Step 4: Since the question asks for complete boxes, we use the whole number result Emma can make 19 complete boxes of cookies. The answer is 19.

6. Emma is organizing a school book fair. She has 348 fiction books and 275 non-fiction books. During the first day of the fair, 189 books were sold. How many books does Emma have left after the first day? Answer: 434 Solution: Find the total number of books Emma had at the start. Emma has 348 fiction books and 275 non-fiction books. Total books = 348 + 275 348 + 275 First, add the ones: 8 + 5 = 13 → write 3, carry over 1 to the tens.
   Full step-by-step solution

   Let's go step-by-step. **Step 1: Find the total number of books Emma had at the start.** Emma has 348 fiction books and 275 non-fiction books. Total books = 348 + 275 Add them: 348 + 275 First, add the ones: 8 + 5 = 13 → write 3, carry over 1 to the tens. Tens: 4 + 7 = 11, plus carried 1 = 12 → write 2, carry over 1 to the hundreds. Hundreds: 3 + 2 = 5, plus carried 1 = 6. So, 348 + 275 = 623. Emma started with 623 books. **Step 2: Subtract the books sold on the first day.** Books sold = 189. Books left = 623 − 189. Subtract: 623 − 189 Ones column: 3 − 9 → need to borrow from tens. Tens column: 2 becomes 1 (after borrowing), so ones column becomes 13 − 9 = 4. Tens column: 1 − 8 → need to borrow from hundreds. Hundreds column: 6 becomes 5 (after borrowing), so tens column becomes 11 − 8 = 3. Hundreds column: 5 − 1 = 4. So, 623 − 189 = 434. **Step 3: Conclusion** Emma has 434 books left after the first day.

7. 2,156 × 48 = ? Answer: 103488 Solution: Multiply 2,156 by 40: 2,156 × 40 = 86,240 Multiply 2,156 by 8: 2,156 × 8 = 17,248 Add the two results: 86,240 + 17,248 = 103,488 The answer is 103,488.
   Full step-by-step solution

   Step 1: Multiply 2,156 by 40: 2,156 × 40 = 86,240 Step 2: Multiply 2,156 by 8: 2,156 × 8 = 17,248 Step 3: Add the two results: 86,240 + 17,248 = 103,488 The answer is 103,488.

8. Liam is saving money to buy a new video game that costs $48.75. He already has $23.50 saved from his allowance. For his birthday, his grandmother gives him $15.25. How much more money does Liam need to buy the video game? Answer: 10.00 Solution: Find the total money Liam has so far. Liam already has $23.50 from his allowance. His grandmother gives him $15.25 for his birthday.
   Full step-by-step solution

   Let's go step-by-step. --- **Step 1: Find the total money Liam has so far.** Liam already has $23.50 from his allowance. His grandmother gives him $15.25 for his birthday. So, total money = 23.50 + 15.25 23.50 + 15.25 = 38.75 --- **Step 2: Find how much more money he needs.** The video game costs $48.75. Money Liam has = $38.75. Money needed = Cost of game − Money he has Money needed = 48.75 − 38.75 --- **Step 3: Perform the subtraction.** 48.75 − 38.75 = 10.00 --- **Step 4: Interpret the result.** Liam needs $10.00 more to buy the video game. --- **Final Answer:** 10.00

9. Liam is saving money to buy a new video game that costs $45.75. He already has $28.50 saved from doing chores. His grandmother gives him $15.25 for his birthday. How much more money does Liam need to buy the video game? Answer: 2.00 Solution: We want to find how much more money Liam needs after adding his savings and birthday money to see if it covers the game's cost. The game costs: $45.75 He already has: $28.50 Grandma gives: $15.25 First, add the money from chores and the birthday money: 28.50 + 15.25 28.50 + 15.00 = 43.50 43.50 +…
   Full step-by-step solution

   Let's go step by step. --- **Step 1: Identify the goal** We want to find how much more money Liam needs after adding his savings and birthday money to see if it covers the game's cost. The game costs: $45.75 He already has: $28.50 Grandma gives: $15.25 --- **Step 2: Add the money Liam has** First, add the money from chores and the birthday money: 28.50 + 15.25 Break it down: 28.50 + 15.00 = 43.50 43.50 + 0.25 = 43.75 So Liam has a total of $43.75 now. --- **Step 3: Find how much more he needs** The game costs $45.75. Subtract the money he has from the cost: 45.75 − 43.75 Break it down: 45.75 − 43.00 = 2.75 2.75 − 0.75 = 2.00 So he needs $2.00 more. --- **Step 4: Verify** Check: Money he has: 43.75 Money needed: 2.00 Total: 43.75 + 2.00 = 45.75 ✔ --- **Final Answer:** 2.00