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:



Answer:
A, y=-6
Step-by-step explanation
Because it isssssssssssssssssssssssssss a watermelon
{ x + 4y = 22 ( + x - x = 0 )
{ - x + 5y = 23
4y + 5y = 22 + 23
9y = 45
y =<u> 45 </u>
9
y = 5
x + 4y = 22
x + 4 . 5 = 22
x + 20 = 22
x = 22 - 20
x = 2
S = { 2 , 5 }
Answer:
2.5 cm
Step-by-step explanation:
We see the diameter is 5cm
so the radius is half the diameter
5/2 = 2.5 cm
Answer:
add like terms the simplified answer is 2m+5p-3
Step-by-step explanation:
lmk if it is not supposed to be simplified