Hello, suganya!

What is the chance that an ordinary year selected at random contains 53 Sundays?

An "ordinary" year has 365 days.

Note that: .

. . That is, a year has 52 full weeks plus one day.

This means that a year begins on a certain weekday

. . and also ends on the same weekday.

Hence, a year starting on Sunday will have 53 Sundays.

Assuming the starting day for a year is evenly distributed,

. . the probability of beginning on a Sunday is