A article is marked at Rs. 65 and a customer buys it for Rs. 56.16 and got two successive discount of 4% and k%. Find the value of   k?

If a : b = 7 : 9 and b : c = 5 : 7, then what is a : c ?

The side of a square is 8 cm. If a square is made by joining the mid points of each sides of this square and this process goes up to infinity. Calculate the sum of areas of all the squares made.

A certain sum becomes Rs. 1020 in 5 years and Rs. 1200 in 8 years at simple interest. What is the value of principal? 

Study the following bar chart and answer the questions carefully.

What is the absolute change in overall sales turnover of the five companies together between 2001 - 2002 and 2002 - 2003 ?

Mohit borrowed Rs. 22000 at 5% simple interest repayable in 5 equal installments. What will be the annual installment payable by him?

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

Greatest among the numbers
$$^{3}\sqrt{9},\sqrt{3},\ ^{4}\sqrt{16},\ ^{6}\sqrt{180}$$ is