1. Your father said, if in one grading period your grade in Math is 90 and above, he
will add Php 50 to your daily allowance. Php 20 if your grade is 80 - 89, but decrease
it by Php 10 if your grade is 79 and below. If the probability to get 90 and above is
12%, while you have 45% chance to get 80-89,
a. What is your expected additional allowance per quarter?
b. What is the variance and standard deviation of the distribution?
c. What do these results in (a) and (b) mean?​