(i) A non-leap year contains 365 (1/4) days 365 (1/4) ÷ 7
= 52 weeks + 1(1/4) days. In 52 weeks,
We get 52 Sundays from the remaining 1(1/4) days we should get one sunday.
∴ The probability of getting the day as Sunday = (5/4)/7 = 5/(4 x 7) = 5/28
(ii) A leap year has 366 days
366/7 = 52 weeks + 2 days
In 52 weeks, we get 52 Sundays.
From the remaining two days we should get one Sunday, the remaining two days can be any one of the following combinations.
Saturday and Sunday, Sunday and Monday, Monday and Tuesday, Tuesday and Wednes¬day, Wednesday and Thursday, Thursday and Friday, Friday and Saturday of the seven combination two have Sundays.
∴ (Probability of getting a Sunday) = 2/7
Selecting a leap year = 1/4
{∴ In every four consecutive years we get one leap year}
∴ Probability of getting 53 Sundays = (2/7) x (1/4) x (1/14)
