You want to put a 5 inch thick layer of topsoil for a new 35 ft by 20 ft garden. The dirt store sells by the cubic yards. How many cubic yards will you need to order?

Question

You want to put a 5 inch thick layer of topsoil for a new 35 ft by 20 ft garden. The dirt store sells by the cubic yards. How many cubic yards will you need to order? The store only sells in increments of 1/4 cubic yards.

Answer 1

V = (35')(20')(5'/12)

V = 291 2/3 ft³

1 yd³ = 27 ft³

291 2/3 ft³ / 27 ft³ ≈ 10.80

Answer 2

So the problem gives you the volume of the space you are trying to fill with soil ( 35ft by 20 ft by 5 in). Lets first put everything into terms of feet and then convert our volume to yards. So 5 inches in terms of feet is 5/12 which equals approximately (rounding to 4 decimal places) 0.4167 so that times 20 times 35 is your volume which is aproximately (rounding to two decimal places) 291.67 cubic feet. There are 3 feet in 1 yard so we divide by 3 to see this volume in yards which gives us 97.222 cubic yards. If the store only sells in increments of 1/4 cubic yards you will need 97.25 cubic yards.