# Mr. 'X' has three children. The birthday of the first child falls on the 5th Monday of April, that of the second one falls on the 5th Thursday of Nove

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Mr. 'X' has three children. The birthday of the first child falls on the 5th Monday of April, that of the second one falls on the 5th Thursday of November. On which day is the birthday of his third child, Which falls on 20th December ?
1. Monday
2. Thursday
3. Saturday
4. Sunday

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Correct Answer - Option 2 : Thursday

5th Monday of April is possible only on two dates : 29th April or 30th April

Case 1 : 29th April Monday

No. of days from 30th April to 1st November = ( 1 + 31 + 30 + 31 + 31 + 30 + 31 + 1 ) = 186 Days

No. of odd days = 186

÷ 7 = 26 weeks and 4 odd days

1 November = Friday

29th November and 30th November are Friday and Saturday respectively.

So, in this case 5th Thursday is not possible.

Case 2 :  30th April Monday

No. of days from 1st May to 1st November = ( 31 + 30 + 31 + 31 + 30 + 31 + 1 ) = 185 Days

No. of odd days = 185  ÷ 7 = 26 weeks and 3 odd days

So, 1st November will be Thursday.

Therefore, 29th November will be 5th Thursday. Birthday of second child is on 29th November.

Thursdays in December = 6th December, 13th December, 20th December, 27th December.

Hence, Thursday is the correct answer.