Question

the bulb manufactured by a company gave a mean life of 3000 hours with standard deviation of 400 hours . if a bulb is selected at eandom, what is the probability it will have a mean life less than 2000 hours? so how can calculate the prabobility

Answer 1

By seeing the data we can see this is normal distribution

Due to symmetry

probability it willhave a mean life less than 2000 hours is 0.4938