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 policeman spotted a thief 200 meter apart. The thief starts running at the speed of 10km/hr. and e policeman chases him at the respectively 11 km/hr. Then find the distance between them after 6 minute -

If x = 2 then the value of $$ x^3 + 27x^2 + 243x + 631$$ is:

If a = 2.234, b = 3.121 and c = –5.355, then the value of $$ a^3 + b^3 + c^3 – 3abc$$ is

Suresh is half his father’s age. After 20 years, his father’s age will be one and a half times Suresh’s age. What is his father’s age now?

The ratio of number of men and women in a factory of 720 workers is 7 : 5. How many more women should be joined to make the ratio 1 : 1?

A, B and C entered into a business and their investment ratio was 5 : 4 : 3. After 4 months B invested Rs. 1000 more and after 8 months C invested Rs. 2000 more. At the end of one year the profit ratio was 15 : 14 : 11, then the investment of C at the beginning was -  

In 50 gm alloy of gold and silver. the gold is 80% by weight. How much gold should be mixed to this alloy so that the weight of gold would become 95%?