(a)[3]
Find the probability that, over a week of 7 days, Cooper wears a blue jumper on at least 5 days.
(b)[5]
Use an appropriate approximation to find the probability that, in a 150-day period, Cooper does not wear a jumper on fewer than 22 days.
Mathematics 9709 · AS & A Level · Discrete random variables
Discrete random variables — practice question
On any day, Cooper either puts on a blue jumper, puts on a green jumper, or does not put on a jumper. The probability that he puts on a blue jumper is $0.6$ and the probability that he puts on a green jumper is $0.3$. What Cooper wears, or does not wear, on one day is independent of his decision on any other day.