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Question
If a leap year is selected at random, what is the chance that it will contain 53 Tuesdays?
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Solution
A leap year has 366 days. It has 52 full weeks and 2 days left.
Both these days can be written as follows-
= {(Monday, Tuesday), (Tuesday, Wednesday), (Wednesday, Thursday), (Thursday, Friday), (Friday, Saturday), (Saturday, Sunday), (Sunday, Monday)}
Total number of such groups = 7
Out of these, Tuesday comes twice. i.e. (Monday, Tuesday), (Tuesday, Wednesday)
So the probability of having 53 Tuesdays in a leap year = `2/7`
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