A cylindrical well of depth 21 m with internal radius of 13 m is dug up. The mud, so detained, is spread evenly to form a platform of dimension 52 × 13.2. What is the height of the platform?

Akshita is at Delhi and Rajat is at gurgaon. Started towards each other, if the ratio of their speed be 8 : 13 respectively then what is the ratio of distance covered by A and B respectively till the point of meeting?

∆ABC is a right angle triangle BD⊥AC. If AD = 12 cm and DC = 8, then BD = ?

If the compound interest on a certain sum for 2 years at 4% p.a. is Rs. 102, the simple interest at the same rate of interest for two years would be:

If two numbers are respectively 20% and 50% of a third number, what is the percentage of the first number to the second?

When the price of an audio system was reduced by 20%, the sale increased by 80%. What was the net effect on the sale?

In a company, there are 75% skilled workers and remaining ones are unskilled. 80% of skilled workers and 20% of unskilled workers are permanent. If number of temporary workers is 126, then what is the number of total workers?

A invested 125% as much money as B. C invested 80% as much money as B. The total of all the three is 61,000. How much did C invest?