Question

The manager at a car assembly plant believes that the mean assembly time for a car is greater than the target time of 35 hours. We record the assembly times for a sample of ten cars. The mean and standard deviation assembly times of these ten cars are calculated to be 37 hours and 5 hours, respectively. Assembly times are known to follow a normal distribution. At the 5% level of significance, we have:

Question 13 options:

	A) insufficient evidence that the true mean assembly time is greater than 35 hours, since the P-value is between 0.05 and 0.10.
	B) sufficient evidence that the true mean assembly time is greater than 35 hours, since the P-value is between 0.10 and 0.15.
	C) insufficient evidence that the true mean assembly time is greater than 35 hours, since the P-value is between 0.10 and 0.15.
	D) sufficient evidence that the true mean assembly time is greater than 35 hours, since the P-value is between 0.20 and 0.30.
	E) insufficient evidence that the true mean assembly time is greater than 35 hours, since the P-value is between 0.20 and 0.30.

Answer 1

P-value = P{Z < }

= P(Z < -1.265)

= 0.103

At the 5% level of significance, we have insufficient evidence that the true mean assembly time is greater than 35 hours, since the P-value is between 0.10 and 0.15