statistics

Question

The standard deviation for a population is σ=7.47. A random sample selected from this population gave a mean equal to 49.63. Construct a 95% confidence interval for μ assuming n=100.

Round your answers to two decimal places

Answer 1

Hi BrookeQ,

 

The confidence interval, CI, formula is as follows:

 

CI = xbar +/- (z*sd/sqrt(n))

 

xbar = 49.63

sd = 7.47

z for 95% = 1.96

n = 100

CI₉₅ = 49.63 +/- (1.96*7.47/sqrt(100))

= 49.63 +/- 1.46

CI₉₅ = (48.17, 51.09)