Quantitative Aptitude - Arithmetic Ability Questions

A merchant changed his trade discount from 25% to 15%. This would increase selling price by

Three pipe P, Q and R can fill a tank in 12 minutes, 18 minutesand 24 minutes respectively. The pipe R is closed 12 minutesbefore the tank is filled. In what time the tank is full?

The average age of 40 students of a class is 16 years. If the average age of 24 students is 15.5 years and that of the 15 students is 16 2⁄3 years, then the age of 40th student is

The value of (2+32-3-342) is

A can complete a work in 20 days and B can complete the same work in 25 days. If both of them work together, then in 3 days what percent of the total work will be completed?

The bus fare between two cities is increased in the ratio 11:18. What would be the increase in the fare, if the original fare is Rs 550?

Slope of the line AB is -4/3. Co-ordinates of points A and B are (x, -5) and (-5, 3) respectively. What is the value of x?

What is the length of the side of an equilateral triangle, if its area is 36√3 sq cm?