(2/9 shirt)/(3 3/5 minute)
= (2/9)/(18/5) shirt/minute
= (2/9)*(5/18) shirt/minute
= 5/81 shirt/minute
5/81 of Brian's shirt is ironed each minute
_____
It will take Brian 16 1/5 minutes to iron his shirt.
a. This information is given to you.
b. We want to find

so we first transform
to the standard normal random variable
with mean 0 and s.d. 1 using

where
are the mean/s.d. of
. Now,

where
is the CDF for
.
c. The 76th percentile is the value of
such that

Transform
to
and apply the inverse CDF of
.





Y=-2/19x-13/19 is the answer