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:30 and 7
Step-by-step explanation:
Answer:
Mean 160
Standard deviation 2.63
Step-by-step explanation:
The Central Limit Theorem estabilishes that, for a random variable X, with mean 
and standard deviation 
, the sample means with size n of at least 30 can be approximated to a normal distribution with mean and standard deviation 
In this problem, we have that:
Find the mean and standard deviation of the sampling distribution of sample means with sample size n = 58.
Mean 160
Standard deviation 
If 8%=96cents, 100%=1200cents total amount=price=tax=1200=96=1296cents =$12.96 answer:12.96
