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The probability that a leap year will have only 52 Sundays is

  • A. 4/7
  • B. 5/7
  • C. 6/7
  • D. 1/7

Profile image of Aniket Singh
9 Months agoGrade
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1 Answer

Profile image of Askiitians Tutor Team
ApprovedApproved Tutor Answer9 Months ago

The probability of a leap year having only 52 Sundays can be determined by understanding how many days are in a leap year and how they distribute across the week.

Leap Year Basics

A leap year consists of 366 days, which is 52 weeks and 2 extra days. This means that in a leap year, there are typically 52 Sundays, plus the possibility of 2 additional days that could also be Sundays.

Extra Days Analysis

The two extra days can be any of the following combinations:

  • Sunday and Monday
  • Monday and Tuesday
  • Tuesday and Wednesday
  • Wednesday and Thursday
  • Thursday and Friday
  • Friday and Saturday
  • Saturday and Sunday

From these combinations, we can see that only the pairs "Saturday and Sunday" and "Sunday and Monday" include a Sunday. Therefore, there are 2 favorable outcomes where there is an additional Sunday out of a total of 7 possible combinations of extra days.

Calculating the Probability

The probability of having only 52 Sundays is the number of combinations without a Sunday divided by the total combinations:

Probability = (Total combinations - Favorable combinations) / Total combinations

So, the probability is:

Probability = (7 - 2) / 7 = 5/7

Final Answer

The correct answer is B. 5/7.