Multiply 2-Digit by 2-Digit

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

1. Ava is helping her teacher organize the classroom library. She has 36 bookshelves, and each bookshelf can hold 25 books. How many books can the classroom library hold in total? Answer: 900 Solution: Identify the numbers to multiply: 36 bookshelves × 25 books per shelf Multiply 36 by 25 First multiply 36 × 20 = 720 Then multiply 36 × 5 = 180 Add the partial products: 720 + 180 = 900 The classroom library can hold 900 books in total.
   Full step-by-step solution

   Step 1: Identify the numbers to multiply: 36 bookshelves × 25 books per shelf Step 2: Multiply 36 by 25 Step 3: First multiply 36 × 20 = 720 Step 4: Then multiply 36 × 5 = 180 Step 5: Add the partial products: 720 + 180 = 900 Step 6: The classroom library can hold 900 books in total.

2. 34 × 56 = ? Answer: 1904 Solution: Multiply 34 by 6 (the ones digit of 56) 34 × 6 = 204 Multiply 34 by 50 (the tens digit of 56) 34 × 50 = 1700 204 + 1700 = 1904 The answer is 1904.
   Full step-by-step solution

   Step 1: Multiply 34 by 6 (the ones digit of 56) 34 × 6 = 204 Step 2: Multiply 34 by 50 (the tens digit of 56) 34 × 50 = 1700 Step 3: Add the two partial products 204 + 1700 = 1904 The answer is 1904.

3. A school is organizing a field trip and needs to pack lunches. Each student will receive a lunch box containing 15 carrot sticks and 12 cherry tomatoes. If 48 students are going on the trip, how many total vegetable pieces need to be prepared? Answer: 1296 Solution: Find how many vegetable pieces each student gets: 15 carrot sticks + 12 cherry tomatoes = 27 vegetable pieces per student Multiply the number of vegetable pieces per student by the number of students: 27 × 48 Break down the multiplication: 27 × 48 = 27 × (40 + 8) = (27 × 40) + (27 × 8) Calculate…
   Full step-by-step solution

   Step 1: Find how many vegetable pieces each student gets: 15 carrot sticks + 12 cherry tomatoes = 27 vegetable pieces per student Step 2: Multiply the number of vegetable pieces per student by the number of students: 27 × 48 Step 3: Break down the multiplication: 27 × 48 = 27 × (40 + 8) = (27 × 40) + (27 × 8) Step 4: Calculate 27 × 40 = 1080 Step 5: Calculate 27 × 8 = 216 Step 6: Add the results: 1080 + 216 = 1296 The answer is 1296.

4. 57 × 84 = ? Answer: 4788 Solution: Multiply 57 by 4 (the ones digit of 84) 57 × 4 = 228 Multiply 57 by 80 (the tens digit of 84) 57 × 80 = 4560 228 + 4560 = 4788 The answer is 4788.
   Full step-by-step solution

   Step 1: Multiply 57 by 4 (the ones digit of 84) 57 × 4 = 228 Step 2: Multiply 57 by 80 (the tens digit of 84) 57 × 80 = 4560 Step 3: Add the two partial products together 228 + 4560 = 4788 The answer is 4788.

5. 34 × 27 = ? Answer: 918 Solution: Multiply 34 by 7 (the ones digit of 27) 34 × 7 = 238 Multiply 34 by 20 (the tens digit of 27) 34 × 20 = 680 238 + 680 = 918 The answer is 918.
   Full step-by-step solution

   Step 1: Multiply 34 by 7 (the ones digit of 27) 34 × 7 = 238 Step 2: Multiply 34 by 20 (the tens digit of 27) 34 × 20 = 680 Step 3: Add the two partial products together 238 + 680 = 918 The answer is 918.

6. A rectangular swimming pool is drawn on a grid. The longer side measures 28 units and the shorter side measures 15 units. If each grid unit represents 2 feet, what is the actual area of the pool in square feet? Answer: 1680 Solution: Area on grid = length × width = 28 × 15 28 × 15 = 28 × (10 + 5) = (28 × 10) + (28 × 5) = 280 + 140 = 420 square units Each grid unit represents 2 feet, so each square unit represents (2 × 2) = 4 square feet Actual area = grid area × scale factor = 420 × 4 420 × 4 = (400 × 4) + (20 × 4) = 1600 +…
   Full step-by-step solution

   Step 1: Find the area of the pool on the grid Area on grid = length × width = 28 × 15 28 × 15 = 28 × (10 + 5) = (28 × 10) + (28 × 5) = 280 + 140 = 420 square units Step 2: Apply the scale factor Each grid unit represents 2 feet, so each square unit represents (2 × 2) = 4 square feet Step 3: Calculate the actual area Actual area = grid area × scale factor = 420 × 4 420 × 4 = (400 × 4) + (20 × 4) = 1600 + 80 = 1680 square feet The answer is 1680.

7. A rectangular swimming pool is drawn on a grid where each square unit represents 1 square meter. The pool has a length of 28 meters and a width of 15 meters. What is the total area of the swimming pool in square meters? Answer: 420 Solution: The area of a rectangle is found by multiplying length × width Length = 28 meters, Width = 15 meters Calculate 28 × 15 First multiply 28 × 10 = 280 Then multiply 28 × 5 = 140 Add the partial products: 280 + 140 = 420 The total area is 420 square meters
   Full step-by-step solution

   Step 1: The area of a rectangle is found by multiplying length × width Step 2: Length = 28 meters, Width = 15 meters Step 3: Calculate 28 × 15 Step 4: First multiply 28 × 10 = 280 Step 5: Then multiply 28 × 5 = 140 Step 6: Add the partial products: 280 + 140 = 420 Step 7: The total area is 420 square meters