Question

Helena uses a mixture of compost and topsoil in her garden. She purchased a total of 10 cubic yards of compost and topsoil for $180. If compost costs $25 per cubic yard and topsoil costs $15 per cubic yard, how many cubic yards of topsoil did she purchase?

Answer 1

Answer:

Let x= cubic yards of top soil them, 10-x= cubic yards of compost Then,

$(10 - x) \times 25 + x \times 15 = 180$

Solving this equation for x will give you the cubic yards of top soil

Answer 2

Answer:

Let the amount of cubic yards of compost be x

Let the amount of cubic yards of topsoil be y

25x+15y=180

x+y=10

You will get these equations first then after solving them

x=3

y=7

Hence there will be 7 cubic yards of topsoil.