Multiply 4-Digit by 1-Digit

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Multiply 4-Digit by 1-Digit · Grade 4 · Worksheet 1

1. A school is organizing a field trip and needs to buy snacks for all 24 classes. Each class has 35 students. How many snacks does the school need to buy in total? Answer: 840 Solution: We have 24 classes, and each class has 35 students. We want the total number of snacks so that each student gets one snack. Identify the operation.
   Full step-by-step solution

   Step 1: Understand the problem. We have 24 classes, and each class has 35 students. We want the total number of snacks so that each student gets one snack. Step 2: Identify the operation. To find the total number of snacks, we multiply the number of classes by the number of students per class. Step 3: Write the multiplication. Total snacks = 24 × 35 Step 4: Break down the multiplication for clarity. We can split 35 into 30 + 5: 24 × 35 = 24 × (30 + 5) Step 5: Multiply each part. First, 24 × 30 = 720 Next, 24 × 5 = 120 Step 6: Add the results. 720 + 120 = 840 Step 7: State the final answer. The school needs to buy 840 snacks in total.

2. Isabella is packing gift bags for her birthday party. She puts 7 stickers in each bag. If she makes 2,472 bags, how many stickers does she use in total? Answer: 17,304 Solution: Isabella puts 7 stickers in each bag and makes 2,472 bags. To find the total number of stickers, multiply the number of bags by the number of stickers per bag: 2,472 × 7. Multiply the ones: 2 × 7 = 14.
   Full step-by-step solution

   Step 1: Isabella puts 7 stickers in each bag and makes 2,472 bags. To find the total number of stickers, multiply the number of bags by the number of stickers per bag: 2,472 × 7. Step 2: Multiply the ones: 2 × 7 = 14. Write 4, carry 1. Step 3: Multiply the tens: 7 × 7 = 49, plus the carried 1 = 50. Write 0, carry 5. Step 4: Multiply the hundreds: 4 × 7 = 28, plus the carried 5 = 33. Write 3, carry 3. Step 5: Multiply the thousands: 2 × 7 = 14, plus the carried 3 = 17. Write 17. Step 6: The total is 17,304. Isabella uses 17,304 stickers in total.

3. 345 × 67 = ? Answer: 23115 Solution: Multiply 345 by 7 (ones place): 345 × 7 = 2415 Multiply 345 by 60 (tens place): 345 × 60 = 20700 Add the partial products: 2415 + 20700 = 23115 The answer is 23115.
   Full step-by-step solution

   Step 1: Multiply 345 by 7 (ones place): 345 × 7 = 2415 Step 2: Multiply 345 by 60 (tens place): 345 × 60 = 20700 Step 3: Add the partial products: 2415 + 20700 = 23115 The answer is 23115.

4. Aroha is arranging square tiles in a rectangular pattern. She draws a rectangle that is 1,357 tiles long and 3 tiles wide. How many square tiles does Aroha need to fill the entire rectangle? Answer: 4,071 Solution: Identify the length and width of the rectangle. Length = 1,357 tiles, Width = 3 tiles. To find the total number of tiles, multiply the length by the width: 1,357 × 3.
   Full step-by-step solution

   Step 1: Identify the length and width of the rectangle. Length = 1,357 tiles, Width = 3 tiles. Step 2: To find the total number of tiles, multiply the length by the width: 1,357 × 3. Step 3: Multiply the ones: 7 × 3 = 21. Write 1, carry 2 tens. Step 4: Multiply the tens: 5 × 3 = 15, plus the carried 2 = 17. Write 7, carry 1 hundred. Step 5: Multiply the hundreds: 3 × 3 = 9, plus the carried 1 = 10. Write 0, carry 1 thousand. Step 6: Multiply the thousands: 1 × 3 = 3, plus the carried 1 = 4. Write 4. Step 7: The product is 4,071. Aroha needs 4,071 tiles.

5. A school is organizing a field trip and needs to pack lunches. Each student will receive a lunch box containing 3 sandwiches. If there are 428 students going on the trip, how many sandwiches need to be prepared in total? Answer: 1284 Solution: We are told that each student gets 3 sandwiches and there are 428 students. We need the total number of sandwiches.
   Full step-by-step solution

   We are told that each student gets 3 sandwiches and there are 428 students. Step 1: Understand the problem. We need the total number of sandwiches. Since each student gets 3 sandwiches, we multiply the number of students by the number of sandwiches per student. Step 2: Write the multiplication. Total sandwiches = Number of students × Sandwiches per student Total sandwiches = 428 × 3 Step 3: Perform the multiplication. First, multiply 400 × 3 = 1200. Then, multiply 28 × 3 = 84. Now add them: 1200 + 84 = 1284. Alternatively, you can multiply directly: 428 × 3: 3 × 8 = 24 → write down 4, carry over 2. 3 × 2 = 6, plus the carried 2 = 8. 3 × 4 = 12. So the result is 1284. Step 4: Conclusion. The total number of sandwiches needed is 1284.

6. A school is organizing a field trip and needs to buy snacks for all 348 students. If each student receives a snack pack that costs $2, how much money will the school spend on snacks? Answer: 696 Solution: We know there are 348 students, and each student gets a snack pack costing $2. We need to find the total cost. Set up the calculation.
   Full step-by-step solution

   Step 1: Understand the problem. We know there are 348 students, and each student gets a snack pack costing $2. We need to find the total cost. Step 2: Set up the calculation. Total cost = (Number of students) × (Cost per snack pack) Total cost = 348 × 2 Step 3: Perform the multiplication. First, multiply 300 × 2 = 600 Then multiply 48 × 2 = 96 Step 4: Add the results. 600 + 96 = 696 Step 5: State the final answer. The school will spend $696 on snacks.

7. A toy factory produces 1,245 toy cars each day. If the factory operates 6 days a week, how many toy cars does it produce in one week? Answer: 7470 Solution: The factory produces 1,245 toy cars each day. The factory operates 6 days a week. To find the total weekly production, multiply the daily production by the number of days: 1,245 × 6.
   Full step-by-step solution

   Step 1: The factory produces 1,245 toy cars each day. Step 2: The factory operates 6 days a week. Step 3: To find the total weekly production, multiply the daily production by the number of days: 1,245 × 6. Step 4: First, multiply 6 by the ones place: 6 × 5 = 30. Write down 0, carry over 3. Step 5: Multiply 6 by the tens place: 6 × 4 = 24. Add the carried over 3: 24 + 3 = 27. Write down 7, carry over 2. Step 6: Multiply 6 by the hundreds place: 6 × 2 = 12. Add the carried over 2: 12 + 2 = 14. Write down 4, carry over 1. Step 7: Multiply 6 by the thousands place: 6 × 1 = 6. Add the carried over 1: 6 + 1 = 7. Write down 7. Step 8: The final product is 7,470. The factory produces 7,470 toy cars in one week.

8. Tane is looking at a rectangular park drawn on a map. The park has a length of 1,248 meters and a width of 9 meters. What is the total area of the park in square meters? Answer: 11,232 Solution: The formula for the area of a rectangle is: Area = length × width. Substitute the given values: Area = 1,248 × 9.
   Full step-by-step solution

   Step 1: The formula for the area of a rectangle is: Area = length × width. Step 2: Substitute the given values: Area = 1,248 × 9. Step 3: Multiply 1,248 by 9: 1,248 × 9 = (1,000 × 9) + (200 × 9) + (40 × 9) + (8 × 9) = 9,000 + 1,800 + 360 + 72 = 11,232. Step 4: The total area of the park is 11,232 square meters. The answer is 11,232.