CAT Calendar Questions

Question

How many of the following statements have to be true?

1. No year can have 5 Sundays in the month of May and 5 Thursdays in the month of June
2. If Feb 14^th of a certain year is a Friday, May 14^th of the same year cannot be a Thursday
3. If a year has 53 Sundays, it can have 5 Mondays in the month of May

A.      0

B.      1

C.      2

D.      3

Answer: Choice (B)

Explanation

                  

                  I.            No year can have 5 Sundays in the month of May and 5 Thursdays in the month of June

A year has 5 Sundays in the month of May => it can have 5 each of Sundays, Mondays and Tuesdays, or 5 each of Saturdays, Sundays and Mondays, or 5 each of Fridays, Saturdays and Sundays. Or, the last day of the Month can be Sunday, Monday or Tuesday.

Or, the 1^st of June could be Monday, Tuesday or Wednesday. If the first of June were a Wednesday, June would have 5 Wednesdays and 5 Thursdays. So, statement I need not be true.

                II.            If Feb 14^th of a certain year is a Friday, May 14^th of the same year cannot be a Thursday

From Feb 14 to Mar 14, there are 28 or 29 days, 0 or 1 odd day

Mar 14 to Apr 14, there are 31 days, or 3 odd datys

Apr 14 to May 14 there are 30 days or 2 odd days

So, Feb 14 to May 14, there are either 5 or 6 odd days

So, if Feb 14 is Friday, May 14 can be either Thursday or Wednesday. So, statement 2 need not be true.

             III.            If a year has 53 Sundays, it can have 5 Mondays in the month of May

Year has 53 Sundays => It is either a non-leap year that starts on Sunday, or leap year that starts on Sunday or Saturday.

Non-leap year starting on Sunday: Jan 1^st = Sunday, jan 29^th = Sunday. Feb 5^th is Sunday. Mar 5^th is Sunday, Mar 26 is Sunday. Apr 2^nd is Sunday. Apr 30^th is Sunday, May 1^st is Monday. May will have 5 Mondays.

So, statement C can be true.

Only one of the three statements needs to be true. Answer Choice (B)