5 In a certain area in the Arctic the probability that it snows on any given day is 0.7 , independent of all other days.
- Find the probability that in a week (7 days) it snows on at least five days.
A week in which it snows on at least five days out of seven is called a 'white' week. - Find the probability that in three randomly chosen weeks at least one is a white week.
In a different area in the Arctic, the probability that a week is a white week is 0.8 . - Use a suitable approximation to find the probability that in 60 randomly chosen weeks fewer than 47 are white weeks.