Question

The same sample of 25 seniors from the urban school district with the mean and standard deviation N(450, 100). A 95% confidence interval for µ for the population of seniors with a margin of error of ± 25 is used. What is the smallest sample size we can take to achieve this same margin of error?

26

45

50

62

69

Answer 1

@sourwing

Answer 2

@eliassaab

Answer 3

@wio

Answer 4

@e.mccormick

Answer 5

Do you know the definition of margin of error in this case?

Answer 6

more of a given......

Answer 7

There is a formula here that I have somewhat forgotten, but we need to continue.

Answer 8

ill tell you

Answer 9

I know we have it. But if we have a formula for margin of error we can solve for varaibles in that formula.

Answer 10

XBAR PLINUS Z = MArgin of error/SQUAREroot standard devition

Answer 11

PLINUS?

Answer 12

haha ill show you

Answer 13

do you see what i mean by plinus now?

Answer 14

then you can plug in

Answer 15

Okay hold on

Answer 16

you need the z score for 95% confidence interval