A batch of 5000 electric lamps has been a mean of 1000 hours and a standard deviation of 75 hours.

Assuming a normal distribution a) how many lamps will fall before 900 hours b) how many lamps will fall between 950 and 1025c)what is proportional wil

Assuming a normal distribution
a) how many lamps will fall before 900 hours
b) how many lamps will fall between 950 and 1025
c)what is proportional will fall between 950 and 980

or:Assuming a normal distribution a) how many lamps will fall before 900 hours b) how many lamps will fall between 950 and 1025c)what is proportional will fall between 950 and 980

Tags:normal,