Question

PLEASE HELP!

You work for a landscaper that has a customer needing to seed an area of land 80 feet by 40 feet in size. The garden center has 5-pound bags of grass seed. Each bag of seed can cover 25 square yards of land.

You calculate that the area you need to seed is 3200 square feet. You divide by 25 to find that you need 128 bags to seed the area. Is this correct?
A) Yes.
B) No, you need to convert the 3200 square feet to yards by dividing by 3. Then calculate the number of bags.
C) No, you need to convert the 3200 square feet to yards by dividing by 9. Then calculate the number of bags.
D) No, you need to convert the 3200 square feet to yards by multiplying by 9. Then calculate the number of bags.

Answer 1

Since the mulch is measured in yards you need to either convert the area to be seeded to yards or the bag to feet. No, you need to convert the 3200 square feet to yards by dividing by 9. Then calculate the number of bags.

Answer 2

1 yard = 3 feet
(1 yard)^2 = (3 feet)^2 ... square both sides
1 yard^2 = 9 feet^2
which means 1 square yard is equal to 9 square feet
think of a square yard as a 3x3 square where each smaller square is 1 square foot.

To convert from square feet to square yards, we multiply by the conversion factor (1 yard^2/9 feet^2). Or put simply we multiply by 1/9 which is the same as dividing by 9

This is why the answer is choice C.