Decimal Multiplication

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Decimal Multiplication · Grade 5 · Worksheet 1

1. Aroha is selling cookies to raise money. Each box of cookies costs $4 dollars, and Aroha sells 21 boxes. How much money did Aroha raise? Answer: 84 Solution: Number of boxes sold: 21 boxes. Price per box: $4. Total money raised: 21 × 4 = 84.
   Full step-by-step solution

   Step 1: Number of boxes sold: 21 boxes. Step 2: Price per box: $4. Step 3: Total money raised: 21 × 4 = 84. Aroha raised $84.

2. Tom is buying 10 packs of stickers for a school project. Each pack costs $1 dollars. How much will Tom spend in total? Answer: 10 Solution: Identify the number of packs: 10 packs. Identify the cost per pack: $1 per pack. Multiply to find the total: 10 × 1 = 10.
   Full step-by-step solution

   Step 1: Identify the number of packs: 10 packs. Step 2: Identify the cost per pack: $1 per pack. Step 3: Multiply to find the total: 10 × 1 = 10. The total cost is $10.

3. A rectangular swimming pool is drawn on a coordinate plane with corners at (1.5, 2), (7.5, 2), (7.5, 5.8), and (1.5, 5.8). Each unit on the grid represents 1 meter. What is the area of the swimming pool in square meters? Answer: 22.8 Solution: Find the length of the rectangle by calculating the difference in x-coordinates: 7.5 - 1.5 = 6 meters Find the width of the rectangle by calculating the difference in y-coordinates: 5.8 - 2 = 3.8 meters Multiply the length and width to find the area: 6 × 3.8 = 22.8 square meters The answer is 22.8.
   Full step-by-step solution

   Step 1: Find the length of the rectangle by calculating the difference in x-coordinates: 7.5 - 1.5 = 6 meters Step 2: Find the width of the rectangle by calculating the difference in y-coordinates: 5.8 - 2 = 3.8 meters Step 3: Multiply the length and width to find the area: 6 × 3.8 = 22.8 square meters The answer is 22.8.

4. Maria is baking cookies for a school fundraiser. Each batch requires 0.375 kilograms of flour. If she plans to bake 12 batches of cookies, how many kilograms of flour does Maria need in total? Answer: 4.5 Solution: Identify the amount of flour needed for one batch: 0.375 kg Identify the number of batches: 12 Multiply to find the total flour needed: 0.375 × 12 Calculate: 0.375 × 12 = 4.5 Maria needs 4.5 kilograms of flour in total.
   Full step-by-step solution

   Step 1: Identify the amount of flour needed for one batch: 0.375 kg Step 2: Identify the number of batches: 12 Step 3: Multiply to find the total flour needed: 0.375 × 12 Step 4: Calculate: 0.375 × 12 = 4.5 Maria needs 4.5 kilograms of flour in total.

5. Liam is building a wooden bookshelf and needs to cut 4 identical shelves from a long board. Each shelf needs to be 1.75 meters long. How many meters of board does Liam need in total for the 4 shelves? Answer: 7 Solution: We are told that Liam needs 4 identical shelves, each 1.75 meters long. We need the total length of board required for all 4 shelves. That means we multiply the length of one shelf by the number of shelves.
   Full step-by-step solution

   We are told that Liam needs 4 identical shelves, each 1.75 meters long. Step 1: Understand the problem We need the total length of board required for all 4 shelves. That means we multiply the length of one shelf by the number of shelves. Step 2: Write the multiplication Total length = 4 × 1.75 Step 3: Break down the multiplication 1.75 is the same as 1 + 0.75 So 4 × 1.75 = 4 × (1 + 0.75) Step 4: Multiply each part 4 × 1 = 4 4 × 0.75 = 4 × (3/4) = 12/4 = 3 Step 5: Add the results 4 + 3 = 7 Step 6: Conclusion Liam needs 7 meters of board in total. Answer: 7

6. Matiu is drawing a rectangular vegetable garden on a coordinate grid. The garden has corners at (2, 4), (8, 4), (8, 6.5), and (2, 6.5). Each unit on the grid represents 1 meter. Matiu wants to cover the entire garden with fertilizer. One bag of fertilizer covers 4 square meters. How many bags does Matiu need to buy? Answer: 4 Solution: Find the length of the rectangle by subtracting the x-coordinates: 8 - 2 = 6 meters. Find the width of the rectangle by subtracting the y-coordinates: 6.5 - 4 = 2.5 meters. Calculate the area: 6 × 2.5 = 15 square meters.
   Full step-by-step solution

   Step 1: Find the length of the rectangle by subtracting the x-coordinates: 8 - 2 = 6 meters. Step 2: Find the width of the rectangle by subtracting the y-coordinates: 6.5 - 4 = 2.5 meters. Step 3: Calculate the area: 6 × 2.5 = 15 square meters. Step 4: Each bag covers 4 square meters. Divide the total area by 4: 15 ÷ 4 = 3.75. Step 5: Since Matiu cannot buy a fraction of a bag, he needs to round up to 4 bags. The answer is 4.

7. 9.28 × 53 = ? Answer: 491.84 Solution: Multiply 9.28 × 53 as if they were whole numbers: 928 × 53 928 × 50 = 46,400 928 × 3 = 2,784 Add the partial products: 46,400 + 2,784 = 49,184 Since 9.28 has two decimal places, the product must also have two decimal places Place the decimal point two places from the right: 491.84 The answer is…
   Full step-by-step solution

   Step 1: Multiply 9.28 × 53 as if they were whole numbers: 928 × 53 Step 2: 928 × 50 = 46,400 Step 3: 928 × 3 = 2,784 Step 4: Add the partial products: 46,400 + 2,784 = 49,184 Step 5: Since 9.28 has two decimal places, the product must also have two decimal places Step 6: Place the decimal point two places from the right: 491.84 The answer is 491.84.

8. Emma is designing a rectangular flower bed on a coordinate grid. The corners are at (1, 1), (9, 1), (9, 5.7), and (1, 5.7). Each unit on the grid represents 1 meter. What is the area of the flower bed in square meters? Answer: 37.6 Solution: Find the length. The x-coordinates of the left and right sides are 1 and 9. Length = 9 - 1 = 8 meters.
   Full step-by-step solution

   Step 1: Find the length. The x-coordinates of the left and right sides are 1 and 9. Length = 9 - 1 = 8 meters. Step 2: Find the width. The y-coordinates of the bottom and top sides are 1 and 5.7. Width = 5.7 - 1 = 4.7 meters. Step 3: Multiply length by width to find the area. 8 × 4.7. Step 4: Multiply 8 × 4 = 32. Multiply 8 × 0.7 = 5.6. Add them: 32 + 5.6 = 37.6. The area of the flower bed is 37.6 square meters.

9. Emma is making friendship bracelets for her classmates. Each bracelet requires 0.35 meters of colorful yarn. If she needs to make bracelets for 12 friends, how many meters of yarn does Emma need in total? Answer: 4.2 Solution: Each bracelet requires 0.35 meters of yarn Emma needs to make 12 bracelets Multiply the yarn per bracelet by the number of bracelets: 0.35 × 12 First multiply 35 × 12 = 420 Since 0.35 has two decimal places, move the decimal point two places to the left: 420 becomes 4.20 4.20 is the same as 4.2…
   Full step-by-step solution

   Step 1: Each bracelet requires 0.35 meters of yarn Step 2: Emma needs to make 12 bracelets Step 3: Multiply the yarn per bracelet by the number of bracelets: 0.35 × 12 Step 4: First multiply 35 × 12 = 420 Step 5: Since 0.35 has two decimal places, move the decimal point two places to the left: 420 becomes 4.20 Step 6: 4.20 is the same as 4.2 The answer is 4.2 meters.