Quantitative Aptitude - Arithmetic Ability Questions

Dodecahedron has 30 edges. How many vertices does it have?

The total surface area of a hemisphere is 462 sq.cm. Find its diameter (in cm).

Two pipes, when working one at a time can fill a cistern in 2 hrs and 3 hrs, respectively while a third pipe can drain the cistern empty in 6 hrs. All the three pipes were opened together when the cistern was 1/6 full. How long will it take for the cistern to be completely full?

Find 2 consecutive natural numbers, sum of whose squares is 25.

In the following question, select the odd word pair from the given alternatives.

If X + Y + Z = 9 then the value of (X -­ 4)3 + (Y -­ 2)3 + (Z -­ 3)3 - 3 (X -­ 4) (Y -­ Z) (Z ­- 3) is

If cosθ = x2-y2x2+y2, then the value of cotθ is

In ΔABC measure of angle B is 90°. If cosecA = 13/12, and AB = 10cm, then what is the length (in cm) of side AC?