Quantitative Aptitude - Arithmetic Ability Questions

A piece of work was finished by A, B and C together. A and B together finished 60% of the work and B and C together finished 70% of the work. Who among the three is most efficient?

If the radius of a circle is increased by 21%, then its area will increase by what percent?

A sum of Rs. 2000 amounts to Rs. 4000 in two years at compound interest. In how many years does the same amount becomes Rs. 8000.

ABCDEF is a regular hexagon of side 12 cm. What is the area (in cm2) of the triangle ECD?

What is the value of tan 7π/6?

If a = 1/a-5, then the value of a + 1/a = ?

If A% of A is 196, then what is the value of A?

Find out the odd word/letters/number/number pair from the given alternatives.