the margin of error would be what?

Question

The length of time what a space rocket component functions is approximately normally distributed. A sample of 20 of these components showed a mean of 900hours with a standard deviation of 87 hours. A 95% confidence interval for the mean time that the component will function is to be constructed. The margin of error would be what number in decimal form?

Answer 1

The margin of error equation is Z*(standard deviation)/√n

Our critical value is 1.96 (look up .975)

 

=1.96*(87/√20)

=38.129

 

The MoE is equal to +38.129 or -38.129