What is the probability that any non-leap year will have 53 Sundays?
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → \(\frac{1}{7}\)
A non-leap year has 365 days, which is 52 full weeks and 1 extra day. The 52 weeks give 52 Sundays in any case, so a 53rd Sunday comes only if the extra day is a Sunday.
Days in the year: \(365=52\times7+1\), that is, 52 weeks and 1 day
The extra day can be any one of the 7 days of the week, and only one of them is Sunday
Probability of 53 Sundays \(\displaystyle=\frac{1}{7}\)
Tip: A leap year has 366 days, that is, 52 weeks and 2 extra days (such as Saturday-Sunday or Sunday-Monday), so the chance of 53 Sundays in a leap year is \(\frac{2}{7}\), Option (4).