Quantitative Aptitude - Arithmetic Ability Questions

Select the odd number from the given alternatives.

Identify the odd one out from the following:

If two complementary angles are in the ratio of 2:3, find the ratio of square of smaller angle to square of greater angle.

If a -­ b = 6 and ab =16, then a3 -­ b3 is

4*(-­0.1(5.5 + 8.5)) of 0.5 = ?

Two pipes can fill a cistern in 28 and 21 hours respectively and an another pipe can empty 30 gallons of water per hour. All the three pipes working together can fill the empty cistern in 84 hours. What is the capacity (in gallons) of the cistern?

If an equilateral triangle has side 12 cm, then what is the difference (in cm) between the circumradius and inradius?

A man buys 7 shirts at Rs 300 each, 2 trousers at Rs 450 each and 1 pair of shoes at Rs 500 each. What is the average expenditure (in Rs) per article?