If the product of four consecutive natural numbers increased by a natural number p, is a perfect square; then the value of p is: 

A is twice as good a workman as B and B is twice as good a workman as C. If A and B can together finish a piece of work in 4 days, then C can do it by himself in : 

The sum 9 + 16 + 25 + 36 +_______+ 100 is equal to?

Direction: A shopkeeper has some kg. rice of same price. He sold 150 kg. rice at 25 Rs. per kg. and earned a profit of 25%, another 180 kg. rice is sold at a profit of 20% and rest are sold at a loss of 10%. If the shopkeeper earns Rs. 1230 profit on all the rice that he has sold then answers the following question:

If the shopkeeper earns 10% profit instead of 10% loss on the rest rice then find the difference between the old and new profit. 

In what time will the annual simple interest rate at $$ {6{1\over4}{\%}}$$ , 72 rupees becomes 81 rupees?

A reduction of 20% in the price of sugar enables a housewife to purchase 6 kg. more for Rs. 240. What is the original price per kg. of sugar?

In a two digit number if it is known that its unit digit exceeds its tens digit by 2 and that the product of the given number and the sum of its digits is equal to 144, then the number is 

A boat goes 15 km in an hour in still water, and takes thrice the time to cover the same distance upstream. The speed of the current (in km / hr) is –