A company sells apples in packages of 4
44. The masses of the individual apples are normally distributed with a mean of
175

g
175g175, start text, g, end text and a standard deviation of
15

g
15g15, start text, g, end text. Assume that the weights of apples are independent from each other.
Let
T
=
T=T, equals the total weight of
4
44 randomly selected apples.
Find the probability that the total mass is less than
685

g
685g685, start text, g, end text.