In how many years will Rs 2000 become Rs 2420 at 10 percent compound annual interest?

If $$ {2^{2n-1}}={1\over8^{n-3}}$$,then the value of n is:

The average of a,b,c is 20 and that of b,c,d is 25, if d=30, then the value of a is-

A circle and a rectangle have the same perimeter. The sides of the rectangle are 18 cm and 26 cm. The area of the circle is:

How much percent above the cost price should a shopkeeper mark his goods so as to earn a profit of 32% after allowing a discount of 12% on the marked price? 

If $$ {tan3A=cot{(2A+40)}}$$ then find the value of $$ {tan^2{3A}}+{cot^{4}3A}$$.

Find the next term in the series.

1329, 997, 725, 507, 337, ?

Directions: The following questions are accompanied by three statements (A) or (I), (B) or (II), and (C) or (III). You have to determine which statement(s) is/are sufficient/necessary to answer the questions.

What is the non-voting population of a certain country?
A. Only males above 21 years of age can vote.
B. Males above 21 years form 30% of the total population.
C. The total population of the country is 30 million.