A leap year is chosen at random. What is the probability that it has 53 Sundays?

\frac{1}{53}

Correct answerYour answer

\frac{1}{7}

Correct answerYour answer

\frac{2}{7}

Correct answerYour answer

\frac{5}{7}

Correct answerYour answer

Show the answer and explanation

CorrectNot quiteAnswer C

Correct answer: C

366 days are 52 full weeks plus 2 extra days, which are consecutive.
The 7 equally likely pairs are (Sun, Mon), (Mon, Tue), …, (Sat, Sun); 2 of them contain a Sunday, so the probability is $\frac{2}{7}$ .

Worth noting

$\frac{1}{7}$ is the answer for a non-leap year, which has only 1 extra day.

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Explanation