Question
A manufacturer sells a new halogen light, the lifetimes of which are normally distributed with a mean weight of 1400 and standard deviation of 50 hours.
It is intended that 90% of the lights should last longer time of T hours. What is the value of T.
Answer
P(Z<1.2816) Taken from the table
t= 50 x 1.2816 + 1400
t= 1464.08
is this correct
A manufacturer sells a new halogen light, the lifetimes of which are normally distributed with a mean weight of 1400 and standard deviation of 50 hours.
It is intended that 90% of the lights should last longer time of T hours. What is the value of T.
Answer
P(Z<1.2816) Taken from the table
t= 50 x 1.2816 + 1400
t= 1464.08
is this correct