If $${b\over a}=0.7$$ find the value of $${a-b\over a+b}={11\over34}.$$

Study the graphs to answer these questions.
The pie chart shows the percentage of graduate employees in various department of M/S XYZ limited.
The employees in various departments of M/S. XYZ limited. Other than graduate employees are those employees who are either post graduate or undergraduates.

Number of other than graduate employees in Finance and Planning departments together is what percent greater than number of graduate employees in Administration department? (Approx) 

If $$ {x+{1\over x}=7}$$ then $$ {x^{2}+{1\over {x^{2}}}=?}$$

What will come in the place of question mark (?) in the following question?

  $$?=5\sqrt{ \left(243 \right)^2}$$

A is 80% more than B and C is $$48{4\over 7}\%$$ less than the sum of A and B. By what percent is C less than A?

The diameters of two cones are equal. If their slant heights are in the ratio 5: 2, then the ratio of curved surface areas of the cones is _________ .

Mahesh invests a sum of money which becomes Rs. 1344 in 3 years and Rs. 1536 in 7 years. How much had he invested?

A certain sum amounts to Rs. 5,832 in 2 years at 8% per annum compound interest, the sum is: