15x^3+4x^2+14x+12
Multiply 3x by every value in the second bracket. Then multiply 2 by every value in the second bracket. Add like terms. (Only answers with the same square are like terms.)
The volume is 35 inches.
hope i helped
Answer:
a) 
With:


b) 

c) 

d) 


Step-by-step explanation:
For this case we know the following propoertis for the random variable X

We select a sample size of n = 81
Part a
Since the sample size is large enough we can use the central limit distribution and the distribution for the sampel mean on this case would be:

With:


Part b
We want this probability:

We can use the z score formula given by:

And if we find the z score for 89 we got:


Part c

We can use the z score formula given by:

And if we find the z score for 75.65 we got:


Part d
We want this probability:

We find the z scores:



Corresponding sides have the same ratio, so
x/15 = 12/(12+8) = 3/5
x = 15*3/5
x = 9