Aptitude Questions -- 100 Bananas

Question: A man ate 100 bananas in five days, each day eating 6 more than the previous day. How many bananas did he eat on the first day?


Ans: he ate 'x' bananas 1st day...then next four days he eats as following...
x+6, x+12, x+18 and x+24
hence, by summing all these we get,
x+x+6+x+12+x+18+x+24=100
=> 5x+60=100
=> 5x=40
=> x=8
hence, a man ate '8' bananas on 1st day.