Question

(1 point) A random sample of 17 size AA batteries for toys yield a mean of 3.7 hours with standard deviation, 0.9 hours. (a) Find the critical value, t* , for a 99% confidence interval. t* = (b) Find the margin of error for a 99% confidence interval. hour(s). Note: Round off your answer to 2 decimal places.

Answer 1

Solution :

(a)

t_{$\alpha$ /2,df} = 2.921

(b)

Margin of error = E = t_{$\alpha$/2,df} * (s /$\sqrt$n)

= 2.921 * (0.9 / $\sqrt$ 17)

Margin of error = E = 0.64