Question

What is the chance that a leap year selected at random will contain 52 sundays?

Answer 1

In a leap year there are 52 weeks, and two remaining days.

Those two days are consecutive, so there can 7 equally likely pairs.

Among the 7 pairs, (Saturday, Sunday) and (Sunday, Monday) pair will result in 53 Sundays.

So unfavourable pairs are these 2, rest (7–2=5) pairs are favourable.

So the probability = 5/7