Point d would be your answer choice !!
Answer:
A____N____C
AN= NC
4x-7=5x-15
5x-4x= 15-7
x= 8
NC = 5x-15=5(8) – 15 = 40 – 15 = 25
I hope I helped you^_^
Answer:
We are given that The valve was tested on 150 engines and the mean pressure was 7.7 lbs/square inch.
We are also given that the valve was designed to produce a mean pressure of 7.6 lbs/square inch
So,
Null hypothesis:
Alternate hypothesis :
Since n > 30 and population standard deviation is given
So, We will use z test
Formula :
Substitute the values
refer the z table for p value
so, p value is 0.9927
Since it is a two tailed test So, p = 2(1- 0.9927) = 0.0146
α = 0.1
p value< α
So, we reject null hypothesis
Hence There is sufficient evidence at the 0.1 level that the valve does not perform to the specifications