In a college 12% of all the students are interested in sports, 10% of the total students are interested in singing and three-fourth of the total students are interested in dancing and remaining 15 students are not interested in any activity, How many total students are there in the college?

By reducing the circumference of a circle by 50 percent, by what percentage will its area decrease?

In an examination, 93 % of students passed and 259 failed. The total number of students appearing at the examination was: 

A person who spends $$ 16{2\over3}\% $$ of  his income is able to save 1200 per month. His monthly expenses (in) is:  

A man gives 20% of his money to his eldest son, 30% of remaining he gives to his younger son. 10% of the remaining he gives in a school for poor boys still he has Rs.100.80. Find his total sum. 

Find the greatest perfect square number of 5 digits.

0.08% of 120% of 40,000 is equal to___.

Two numbers are 30% and 37% lesser than a third number. By how much percent is the second number to be enhanced to make it equal to the first number?