Fection 6.3 Homework
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Use proportions to solve the following problem.
Question 18, 6.3.47
Part 1 of 2
A 50-pound bag of topsoil will cover a surface area of 12 ft².
a) How many pounds of topsoil are needed to cover a surface area of 600 ft²?
b) How many bags of topsoil must be purchased to cover a surface area of 600 ft²?
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Answer :

Certainly! Let's solve the problem step-by-step:

### Part (a) How many pounds of topsoil are needed to cover a surface area of 600 ft²?

1. Identify the given information:
- A 50-pound bag of topsoil covers 12 square feet.

2. Set up a proportion to find out how many pounds of topsoil are needed to cover 600 square feet:
- If 50 pounds cover 12 square feet, then let [tex]\( x \)[/tex] be the number of pounds needed to cover 600 square feet.
- Write the proportion: [tex]\(\frac{50 \text{ pounds}}{12 \text{ ft}^2} = \frac{x \text{ pounds}}{600 \text{ ft}^2}\)[/tex]

3. Solve the proportion for [tex]\( x \)[/tex]:
[tex]\[ \frac{50}{12} = \frac{x}{600} \][/tex]

4. Cross-multiply and solve for [tex]\( x \)[/tex]:
[tex]\[ 50 \times 600 = 12 \times x \][/tex]
[tex]\[ 30000 = 12x \][/tex]
[tex]\[ x = \frac{30000}{12} \][/tex]
[tex]\[ x = 2500 \text{ pounds} \][/tex]

So, 2500 pounds of topsoil are needed to cover an area of 600 ft².

### Part (b) How many bags of topsoil must be purchased to cover a surface area of 600 ft²?

1. Identify again the given information:
- One bag of topsoil covers 12 square feet.

2. Set up a proportion to find out how many bags are needed for 600 square feet:
- Let [tex]\( y \)[/tex] be the number of bags needed to cover 600 square feet.
- Write the proportion: [tex]\(\frac{1 \text{ bag}}{12 \text{ ft}^2} = \frac{y \text{ bags}}{600 \text{ ft}^2}\)[/tex]

3. Solve the proportion for [tex]\( y \)[/tex]:
[tex]\[ \frac{1}{12} = \frac{y}{600} \][/tex]

4. Cross-multiply and solve for [tex]\( y \)[/tex]:
[tex]\[ 1 \times 600 = 12 \times y \][/tex]
[tex]\[ 600 = 12y \][/tex]
[tex]\[ y = \frac{600}{12} \][/tex]
[tex]\[ y = 50 \text{ bags} \][/tex]

So, 50 bags of topsoil are needed to cover an area of 600 ft².

### Summary:
- 2500 pounds of topsoil are needed to cover 600 ft².
- 50 bags of topsoil are required to cover 600 ft².