posted by Vijay .
A continuously running washing machine receives jolts in a Poisson process at an average rate of 10 jolts per hour. The standard deviation of the number of jolts received in given 20 minute run is equal to
Assume that grades follow a normal distribution (the “bell curve”). It is reasonable to assume
that the mean of this distribution is μ = 75 and the standard variation is ! = 8 .