# statistics

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A random sample of 100 students from a high school was selected. If a 98% confidence interval estimate for the mean age of students is calculated to be 14.2511 to 14.9489, then the standard deviation of the sample mean is?

• statistics -

2E + 14.2511 = 14.9489
2E = 0.6978

E = 0.3489

E = za/2 * s /sqrt(n))

.3489 = 2.33s/10

. 3489 = .233s
s = 1.49742

Standard deviation. = 1.49742

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