Directions : What should come in place of the question mark (?) in the following number series? 

7 17 54 ? 1098 6591 

The total surface area of a solid right circular cylinder is twice that of a solid sphere. If they have the same radii, the ratio of the volume of the cylinder to that of the sphere is given by

A and B can separately complete a piece of work in 20 days and 30 days respectively. They worked together for some time then B left the work. If A completed the rest of the work in 10 days, then B worked for how many days?

In a college the number of students studying Arts, Commerce and Science are in the ratio of 3:5:8 respectively. If the number of students studying Arts, Commerce and Science is increased by 20%, 40%, and 25% respectively, what will be the new ratio of students in Arts, Commerce and Science respectively?

From each of the four corners of a rectangular sheet of dimensions 30 cm × 25 cm, a square of side 2 cm is cut off and a box is made. The volume of the box is

There are 500 students in a school out of which 60% are boys. 40% of the boys play hockey and girls don’t play hockey. 75% of the girls play badminton. If there are only two games to be played, number of students who don’t play any game.

Mr. Khanna took a loan of Rs 10,000 on simple interest for two years at the rate 3% per annum. The total amount that he will be paying as interest in 2 year is 3% of his monthly salary. What his monthly salary?