Answer :(a)
Solution:
100 years contain 5 days.
The last day of a century is Friday.
200 years contain (5x2)
= 15 = 3 odd days.
The last day of the second century is Wednesday.
300 years contain (5x3)
=15 = 1 odd day.
400 years contain 0 odd day
The last day of the 4th century is Sunday.
The cycle is repeated.
The last day of the century cannot be Tuesday or Thursday or Saturday.
Q15. How many days are there in x in weeks x days?