Question

A field test for a new exam was given to randomly selected seniors. The exams were graded, and the sample mean and sample standard deviation were calculated. Based on the results, the exam creator claims that on the same exam, nine times out of ten, seniors will have an average score within 6% of 80%.

Is the confidence interval at 90%, 95%, or 99%? What is the margin of error? Calculate the confidence interval and explain what it means in terms of the situation.

Answer 1

@Loser66

Answer 2

@Hero

Answer 3

I don't know.

Answer 4

Can you mention someone for me please

Answer 5

@jim_thompson5910

Answer 6

the key phrase here is `nine times out of ten` which points us to a 90% confidence interval

Answer 7

90% of the confidence intervals generated will have the population parameter we're interested in

Answer 8

ok

Answer 9

So what would be the margin error

Answer 10

`seniors will have an average score within 6% of 80%`

the target is 80%. Basically this is the stated population parameter

the 6% is the error from the target. You can go 6% too high, or 6% too low