A random sample of 42 textbooks has a mean price of $114.50 and a standard deviation of $12.30.
Find a 98% confidence interval for the mean price of all textbooks.

Step-by-step explanation:

We want to determine a 98% confidence interval for the mean price for textbooks.

Number of sample, n = 42

Mean, u = $114.5

Standard deviation, s = $12.3

For a confidence level of 98%, the corresponding z value is 2.33.

We will apply the formula

Confidence interval

= mean ± z ×standard deviation/√n

It becomes

114.5 ± 2.33 × 12.3/√42

= 114.5 ± 2.33 × 1.898

= 114.5 ± 4.42

The lower end of the confidence interval is 114.5 - 4.42 = 110.08

The upper end of the confidence interval is 114.5 + 4.42 = 118.92

Therefore, with 98% confidence interval, the mean price of all textbooks is between $110.08 and $118.92

the cat is blue because the probability of extension towards the prefix of the diameter of the circle could only mathematically equal to the sum of the roots of the carrots from   your garden.

step-by-step explanation: