Let C be the amount of compost
T be the amount of topsoil
Each compost cost = $25
Cost of C compost = 25C
Each topsoil cost = $15
Cost of T topsoil = 15T
Amount of compost + amount of topsoil = 10
C + T = 10 -------> Equation 1
cost of C compost + cost of T topsoil = 180
25C + 15T = 180 --------> equation 2
Solve the first equation for C
C + T = 10
C = 10 - T
Now plug it in second equation
25C + 15T = 180
25 ( 10 - T) +15T = 180
250 - 25T + 15T = 180 (combine like terms)
250 - 10 T = 180 (Subtract 250 on both sides)
-10T = 180 - 250
-10T = -70 ( divide by -10 on both sides)
T = 7
She purchased 7 cubic yards of topsoil .
Answer:
Step-by-step explanation:
Okay, so this is simple. It just needs steps.
Quotient of 18 and 2 = 9.
Sum of 22 and 9 = 31.
31 - 9 = 22.
