Multiply 4-Digit by 1-Digit

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Multiply 4-Digit by 1-Digit · Grade 4 · Worksheet 2

1. A community garden has 24 rectangular plots for growing vegetables. Each plot measures 15 feet by 12 feet. What is the total area of all the garden plots combined? Answer: 4320 Solution: Area of rectangle = length × width Area of one plot = 15 feet × 12 feet 15 × 12 = 180 square feet Multiply the area of one plot by the total number of plots Total area = 180 square feet × 24 plots 180 × 20 = 3,600 180 × 4 = 720 3,600 + 720 = 4,320 The total area of all garden plots is 4,320…
   Full step-by-step solution

   Step 1: Find the area of one garden plot Area of rectangle = length × width Area of one plot = 15 feet × 12 feet 15 × 12 = 180 square feet Step 2: Multiply the area of one plot by the total number of plots Total area = 180 square feet × 24 plots 180 × 20 = 3,600 180 × 4 = 720 3,600 + 720 = 4,320 The total area of all garden plots is 4,320 square feet.

2. A toy factory produces 1,245 toy cars each day. If the factory operates for 23 days this month, how many toy cars will they produce in total? Answer: 28635 Solution: The factory makes 1,245 cars each day and operates for 23 days. To find the total, multiply the daily production by the number of days: 1,245 × 23. First, multiply 1,245 by 3 (the ones digit of 23): 1,245 × 3 = 3,735.
   Full step-by-step solution

   Step 1: The factory makes 1,245 cars each day and operates for 23 days. Step 2: To find the total, multiply the daily production by the number of days: 1,245 × 23. Step 3: First, multiply 1,245 by 3 (the ones digit of 23): 1,245 × 3 = 3,735. Step 4: Next, multiply 1,245 by 20 (the tens digit of 23): 1,245 × 20 = 24,900. Step 5: Add the two partial products together: 3,735 + 24,900 = 28,635. The total number of toy cars produced is 28,635.

3. The school library is buying new books for the fourth grade classrooms. They need 24 books for each of the 15 classrooms. How many books does the library need to buy in total? Answer: 360 Solution: We need to find the total number of books for 15 classrooms, with each classroom getting 24 books. Write the multiplication.
   Full step-by-step solution

   Step 1: Understand the problem. We need to find the total number of books for 15 classrooms, with each classroom getting 24 books. Step 2: Write the multiplication. Total books = number of classrooms × books per classroom Total books = 15 × 24 Step 3: Break down the multiplication for easier calculation. We can split 24 into 20 + 4. So, 15 × 24 = 15 × (20 + 4) Step 4: Use the distributive property. First, multiply 15 × 20: 15 × 20 = 300 Step 5: Multiply 15 × 4: 15 × 4 = 60 Step 6: Add the two results. 300 + 60 = 360 Step 7: Conclusion. The library needs to buy 360 books in total.

4. A community center is organizing a summer reading program and needs to order books for 24 reading groups. Each group will receive 156 books to share among their members. How many books does the community center need to order in total? Answer: 3744 Solution: Identify the number of groups: 24 reading groups Identify the number of books per group: 156 books Multiply to find the total number of books: 24 × 156 Calculate 24 × 100 = 2400 Calculate 24 × 50 = 1200 Calculate 24 × 6 = 144 Add the partial products: 2400 + 1200 = 3600, then 3600 + 144 = 3744…
   Full step-by-step solution

   Step 1: Identify the number of groups: 24 reading groups Step 2: Identify the number of books per group: 156 books Step 3: Multiply to find the total number of books: 24 × 156 Step 4: Calculate 24 × 100 = 2400 Step 5: Calculate 24 × 50 = 1200 Step 6: Calculate 24 × 6 = 144 Step 7: Add the partial products: 2400 + 1200 = 3600, then 3600 + 144 = 3744 Step 8: The community center needs to order 3744 books in total.

5. A school is organizing a field trip and needs to buy snacks for all the students. There are 24 classes in the school, and each class has 36 students. How many snacks does the school need to buy in total? Answer: 864 Solution: We need to find the total number of snacks for all students. There are 24 classes, and each class has 36 students. So, total snacks = total number of students.
   Full step-by-step solution

   Step 1: Understand the problem. We need to find the total number of snacks for all students. There are 24 classes, and each class has 36 students. So, total snacks = total number of students. Step 2: Calculate total number of students. Total students = number of classes × number of students per class Total students = 24 × 36 Step 3: Break down the multiplication for clarity. First, multiply 24 by 30: 24 × 30 = 720 Step 4: Multiply 24 by 6: 24 × 6 = 144 Step 5: Add the two results: 720 + 144 = 864 Step 6: Conclusion. The school needs to buy 864 snacks in total.

6. 1,234 × 56 = ? Answer: 69104 Solution: Multiply 1,234 by 6 (the ones digit of 56): 1,234 × 6 = 7,404 Multiply 1,234 by 50 (the tens digit of 56): 1,234 × 50 = 61,700 Add the two partial products: 7,404 + 61,700 = 69,104 The final answer is 69,104.
   Full step-by-step solution

   Step 1: Multiply 1,234 by 6 (the ones digit of 56): 1,234 × 6 = 7,404 Step 2: Multiply 1,234 by 50 (the tens digit of 56): 1,234 × 50 = 61,700 Step 3: Add the two partial products: 7,404 + 61,700 = 69,104 Step 4: The final answer is 69,104.

7. A community center is organizing a summer reading program and wants to give each participant a reading kit. Each kit contains 12 books. If 256 children sign up for the program, how many books does the community center need to prepare in total? Answer: 3072 Solution: Identify what you need to find: total number of books Multiply the number of children by the number of books per kit 256 × 12 = ?
   Full step-by-step solution

   Step 1: Identify what you need to find: total number of books Step 2: Multiply the number of children by the number of books per kit Step 3: 256 × 12 = ? Step 4: Break it down: 256 × 10 = 2560 Step 5: Then 256 × 2 = 512 Step 6: Add the results: 2560 + 512 = 3072 Step 7: The community center needs 3072 books in total.

8. A factory produces 245 toy cars each day. If the factory operates 6 days a week, how many toy cars does it produce in one week? Answer: 1470 Solution: The factory produces 245 toy cars each day. It operates 6 days a week. We need to find the total number of toy cars produced in one week.
   Full step-by-step solution

   Step 1: Understand the problem. The factory produces 245 toy cars each day. It operates 6 days a week. We need to find the total number of toy cars produced in one week. Step 2: Set up the calculation. Since the factory makes 245 cars per day and works 6 days a week, we multiply: Total cars in one week = 245 × 6. Step 3: Perform the multiplication. First, break it down: 245 × 6 = (200 × 6) + (40 × 6) + (5 × 6). Step 4: Calculate each part. 200 × 6 = 1200 40 × 6 = 240 5 × 6 = 30 Step 5: Add the results. 1200 + 240 = 1440 1440 + 30 = 1470 Step 6: State the final answer. The factory produces 1470 toy cars in one week.

9. A school is organizing a field trip and needs to order buses. Each bus can carry 48 students. If there are 365 students going on the trip, how many buses are needed to transport all the students? Answer: 8 Solution: We have 365 students, and each bus can carry 48 students. We need to find out how many buses are needed to transport all students. Divide the total number of students by the bus capacity.
   Full step-by-step solution

   Step 1: Understand the problem. We have 365 students, and each bus can carry 48 students. We need to find out how many buses are needed to transport all students. Step 2: Divide the total number of students by the bus capacity. 365 ÷ 48 = ? Step 3: Perform the division. 48 × 7 = 336 365 − 336 = 29 So, 365 ÷ 48 = 7 remainder 29. Step 4: Interpret the result. 7 full buses will carry 336 students, but there are 29 students left over. These 29 students also need a bus, so we need one more bus for them. Step 5: Determine the total number of buses. 7 buses + 1 bus = 8 buses. Step 6: Check the answer. 8 buses × 48 students = 384 seats, which is enough for 365 students. Final answer: 8 buses are needed.