If a-b=1 and a³-b³=61, then the value of ab will be 

Which of the following is a perfect square as well as a cube ? 

The price of sugar is increased by 20 %. If the expenditure on sugar has to be kept the same as earlier, the ratio between the reduction in consumption and the original consumption is: 

A, B and C started a business with their investments in the ratio 1 : 2 : 4 . After 6-month A invested the half amount more as before and B invested same the amount as before while C withdrew $$1\over 4$$th of the his investments. Find the ratio of their profits at the end of the year. 

In the given figure ΔDEF is right angle triangle, ∠G=120° and DG=12 cm , GF=10 cm then find out the value of DF.

An interval of 3 hours 40 minutes is wrongly estimated as 3 hours 45.5 minutes. The error percentage is  

Two bikers A and B start and ride at 75 km/hr and 60 km/hr respectively towards each other. They meet after 20 minutes. How far (in km) were they from each other when they started?

A sum becomes Rs. 2916 in 2 years at 8 % per annum compound interest. The simple interest at 9% per annum for 3 years on the same amount will be