Question

A research scientist wants to know how many times per hour a certain strand of bacteria reproduces. The mean is found to be 10.2 reproductions and the population standard deviation is known to be 2.1. If a sample of 1731 was used for the study, construct the 99% confidence interval for the true mean number of reproductions per hour for the bacteria. Round your answers to one decimal place.

Answer 1

sample mean 'x̄=	10.2
sample size    n=	1731.00
std deviation σ=	2.100
std errror ='σx=σ/√n=	0.0505

for 99 % CI value of z=		2.576
margin of error E=z*std error =		0.13
lower bound=sample mean-E=		10.1
Upper bound=sample mean+E=		10.3

from above 99% confidence interval for population mean =(10.1,10.3)