If U+V=80 and U:V=5:3 then find out the U-V.

If a wire is bent into the shape of a square, the area of the square is 81 sq. cm. When the wire is bent into a semicircular shape, the area of the semicircle is 

A DVD player was purchased for Rs 4860. At what price should it be sold so that 25% profit is earned?

A boat goes 75 km upstream in 3 hours and 60 km downstream in 1.5 hours. Then the speed of the boat in still water is: 

Twenty five percent of Pranab’s annual salary is equal to eighty percent of Surya’s annual salary. Surya’s monthly salary is forty percent of Dheeru’ monthly salary. If Dhreeu’s annual salary is Rs 6 lacs, what is Pranab’s monthly salary? (At some places annual income and in some place monthly income are given)

A cloth merchant sold half of his cloth at 20 % profit, half of the remaining cloth at 20 % loss and the rest was sold at its cost price. In the total transaction, his gain or loss will be 

A reduction of 20 % in the price of salt enabled a purchaser to obtain 4 kg. more for Rs. 100. The reduced price of salt per kg is :

What will come in place of question mark (?) in the following series?
8, 10, 18, 44, 124, ?