1 using the ztable find the area to the right of z116 2 test

1. using the z-table, find the area to the right of z=-1.16

2. testing indicates that the lifetimes of a certain lot of light bulbs are approximately normally distributed with a mean of 100 hours and a standard deviation of 10 hours.

a. what is the probability that a bulb selected at random will last less than 83 hours?