Question

Question 1

a). i. To estimate the average time it takes to assemble a certain printer component, the industrial engineer at an electronics firm timed 40 technicians in the performance of this task, getting a mean of 12.73 minutes and a standard deviation of 2.06 minutes. Construct a 98% confidence interval for the true average time it takes to assemble the printer component.

ii. A sample of 16 girls gave a mean mass of 35 kg and a standard dev iation of 6 kg. Assumingnormality,constructa96%confidenceintervalfor ?.

iii. A random sample of 20 students obtained a mean of 72 and variance of 16 on a Mathematics examination. Assuming the scores to be normally distributed, construct a 98% confidence interval for?2.

b. Briefly explain the following: i)Critical Region

ii)Confidence Coefficient

iii)Alternative Hypothesis

c. A car manufacturer claims that the average weekly income of owners of his car is $180. An investigator takes a sample of 200 such car owners and finds out that they have an average weekly income of $184.26 with a standard deviation of $24.12. On the basis of the sample, do you agree with the manufacturer’s claim? Test at ? = 5%.

Answer 1

a)

i)

ii)

iii)

we are allowed to solve one question only already solved three here.thank you