Question

We are told that the sample mean xbar=15, SE=5 and zmax=1.6 for our confidence interval. what is our confidence interval

Answer #1

Solution :

Given that,

Z/2 = 1.6

SE = 5

= 15

Margin of error (E) = Z/2* SE

= 1.6 * 5

E = 8

A confidence interval estimate of the population mean is,

- E < < + E

15 - 8 < < 15 + 8

7 < < 23

**(7, 23)**

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