Gina has been observing students at a university. Her data indicate that 60% of the males and 70% of the females are wearing earphones at any given time. She decides to interview randomly selected students and to interview males and females alternately.

a. Use Gina’s observation data to find the probability that the first person not wearing earphones is the third male interviewed, given that she first interviews:

i. A male

ii. A female

iii. A male who is wearing earphones. 

b. State any assumptions made about the wearing of earphones in your calculations for part a.