Multiply 2-Digit by 2-Digit

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

1. Noah is organizing a school field trip to the science museum. Each school bus can carry 36 students, and they need to transport 12 full buses of students. How many students are going to the museum in total? Answer: 432 Solution: Identify the number of buses: 12 buses Identify the number of students per bus: 36 students Multiply the number of buses by the number of students per bus: 12 × 36 Calculate 12 × 30 = 360 Calculate 12 × 6 = 72 Add the partial products: 360 + 72 = 432 There are 432 students going to the museum in…
   Full step-by-step solution

   Step 1: Identify the number of buses: 12 buses Step 2: Identify the number of students per bus: 36 students Step 3: Multiply the number of buses by the number of students per bus: 12 × 36 Step 4: Calculate 12 × 30 = 360 Step 5: Calculate 12 × 6 = 72 Step 6: Add the partial products: 360 + 72 = 432 There are 432 students going to the museum in total.

2. Noah is organizing a school field day and needs to provide water bottles for all the students. There are 36 classes participating, and each class has 24 students. How many water bottles does Noah need to prepare in total? Answer: 864 Solution: Identify the number of classes: 36 Identify the number of students in each class: 24 Multiply the number of classes by the number of students per class: 36 × 24 Calculate 36 × 20 = 720 Calculate 36 × 4 = 144 Add the partial products: 720 + 144 = 864 Noah needs to prepare 864 water bottles in total.
   Full step-by-step solution

   Step 1: Identify the number of classes: 36 Step 2: Identify the number of students in each class: 24 Step 3: Multiply the number of classes by the number of students per class: 36 × 24 Step 4: Calculate 36 × 20 = 720 Step 5: Calculate 36 × 4 = 144 Step 6: Add the partial products: 720 + 144 = 864 Noah needs to prepare 864 water bottles in total.

3. A rectangular swimming pool is drawn on a grid where each square unit represents 1 square meter. The pool's longer side measures 18 meters and its shorter side measures 14 meters. What is the total area of the swimming pool in square meters? Answer: 252 Solution: The area of a rectangle is found by multiplying its length by its width. The length is 18 meters and the width is 14 meters. Multiply 18 × 14.
   Full step-by-step solution

   Step 1: The area of a rectangle is found by multiplying its length by its width. Step 2: The length is 18 meters and the width is 14 meters. Step 3: Multiply 18 × 14. Step 4: First multiply 18 × 10 = 180 Step 5: Then multiply 18 × 4 = 72 Step 6: Add the partial products: 180 + 72 = 252 Step 7: The total area is 252 square meters.

4. 52 × 78 = ? Answer: 4056 Solution: Multiply 52 by 8 (the ones digit of 78) 52 × 8 = 416 Multiply 52 by 70 (the tens digit of 78) 52 × 70 = 3640 416 + 3640 = 4056 The answer is 4056.
   Full step-by-step solution

   Step 1: Multiply 52 by 8 (the ones digit of 78) 52 × 8 = 416 Step 2: Multiply 52 by 70 (the tens digit of 78) 52 × 70 = 3640 Step 3: Add the two partial products together 416 + 3640 = 4056 The answer is 4056.

5. 38 × 72 = ? Answer: 2736 Solution: Multiply 38 by 2 (the ones digit of 72) 38 × 2 = 76 Multiply 38 by 70 (the tens digit of 72) 38 × 70 = 2660 76 + 2660 = 2736 The answer is 2736.
   Full step-by-step solution

   Step 1: Multiply 38 by 2 (the ones digit of 72) 38 × 2 = 76 Step 2: Multiply 38 by 70 (the tens digit of 72) 38 × 70 = 2660 Step 3: Add the two partial products together 76 + 2660 = 2736 The answer is 2736.

6. 23 × 47 = ? Answer: 1081 Solution: Multiply 23 by 7 (the ones digit of 47): 23 × 7 = 161 Multiply 23 by 40 (the tens digit of 47): 23 × 40 = 920 Add the two partial products: 161 + 920 = 1081 The answer is 1081.
   Full step-by-step solution

   Step 1: Multiply 23 by 7 (the ones digit of 47): 23 × 7 = 161 Step 2: Multiply 23 by 40 (the tens digit of 47): 23 × 40 = 920 Step 3: Add the two partial products: 161 + 920 = 1081 The answer is 1081.

7. 78 × 49 = ? Answer: 3822 Solution: Multiply 78 by 9 (the ones digit of 49) 78 × 9 = 702 Multiply 78 by 40 (the tens digit of 49) 78 × 40 = 3120 702 + 3120 = 3822 The answer is 3822.
   Full step-by-step solution

   Step 1: Multiply 78 by 9 (the ones digit of 49) 78 × 9 = 702 Step 2: Multiply 78 by 40 (the tens digit of 49) 78 × 40 = 3120 Step 3: Add the two partial products together 702 + 3120 = 3822 The answer is 3822.

8. A farmer plants 24 rows of corn with 36 corn plants in each row. How many corn plants does the farmer plant in total? Answer: 864 Solution: The farmer plants 24 rows of corn. Each row has 36 corn plants. We need to find the total number of corn plants.
   Full step-by-step solution

   Step 1: Understand the problem. The farmer plants 24 rows of corn. Each row has 36 corn plants. We need to find the total number of corn plants. Step 2: Recognize the operation. To find the total number of plants, we multiply the number of rows by the number of plants in each row. Step 3: Write the multiplication. Total plants = 24 × 36 Step 4: Break down the multiplication for clarity. We can split 36 into 30 + 6 and use the distributive property: 24 × 36 = 24 × (30 + 6) Step 5: Multiply each part separately. First, 24 × 30: 24 × 3 = 72, so 24 × 30 = 720 Next, 24 × 6: 20 × 6 = 120 4 × 6 = 24 120 + 24 = 144 Step 6: Add the two results. 720 + 144 = 864 Step 7: State the final answer. The farmer plants 864 corn plants in total.

9. 47 × 63 = ? Answer: 2961 Solution: Multiply 47 by 3 (the ones digit of 63) 47 × 3 = 141 Multiply 47 by 60 (the tens digit of 63) 47 × 60 = 2820 141 + 2820 = 2961 The answer is 2961.
   Full step-by-step solution

   Step 1: Multiply 47 by 3 (the ones digit of 63) 47 × 3 = 141 Step 2: Multiply 47 by 60 (the tens digit of 63) 47 × 60 = 2820 Step 3: Add the two partial products together 141 + 2820 = 2961 The answer is 2961.