Question

on what date(of the following) of august 1980 did monday fall? a) 18th b) 16 th c) 24th d) 12th

Answer 1

18th well its because 
on july 31st it was thursday,
so how many days in a week 7 
so 7th day will be another thursday
so 7+7=14 after 14 days it will be thursday again now remember how many days in a week
so date august 14th,thursday now after 2 days it will be saturday so after again 2 days it will be monday so [14+2+2] is the equation =18th because there was no other option on monday left 

hope this helps u

Answer 2

a) 18th is the date of August 1980 on which Monday fall.