What is the volume of a cube whose side is 7.5 cm?

If the selling price of a product is multiplied by 2, the resulting profit is 6 times the original profit. What is the original profit percentage?

16 children are to be divided into two group A and B consisting of 10 and 6 children. The average percent marks obtained by the children of Group A is 75 and the average percent marks of all the 16 children is 76. What is the average percent marks of children of Group B?

If   0.8 : X :: 5 : 8, then the value of X is

The area of a triangle with vertices A (0, 8), O (0, 0), and B (5, 0) is :

If x, y, z are three sum of money such that y is the simple interest on x and z is the simple interest on y for the same time and at the same rate of interest, then what is the relation between x, y, z we have – 

If a machine consumes k/5 kilowatts of power every t hours, how much power in kilowatts, will three such machines consume in 10 hours? 

A boat goes 30 km upstream and 44 km downstream in 10 hours. In 13 hours, it can go 40 km upstream and 55 km downstream. The speed of the boat in still water is.