Question

STATISTICS: The mean time was 103.57s, and the standard deviation is 4.52s. If the normal model is appropriate, what percent of times will be less than 99.05s?

Answer 1

\[z=\frac{X-\mu}{\sigma}=\frac{99.05-103.57}{4.52}=-1\]
Now you need to refer to your z-table

Answer 2

@QRAwarrior Are you there?