Quantitative Aptitude - Arithmetic Ability Questions

In the following question, four groups of three numbers are given. In each group the second and third number are related to the first number by a Logic/Rule/Relation. Three are similar on basis of same Logic/Rule/Relation. Select the odd one out from the given alternatives.

Select the odd word/letters/number/number pair from the given alternatives.

If (cosecA -­ 1)/(cosecA + 1) = x, then the value of x is

The compound interest on Rs. 1000 at 10% per annum for 3 years in (Rs.) is

cos(A+B) + cos(A-B) is equal to

The average revenues of 7 consecutive years of a company is Rs 71 lakhs. If the average of first 4 years is Rs 66 lakhs and that of last 4 years is Rs 78 lakhs. What is the revenue for the fourth year.

If ax - 4y = -6 has a slope of -3/2. What is the value of a?

A right circular cylinder has height as 18 cm and radius as 7 cm. The cylinder is cut in three equal parts (by 2 cuts parallel to base). What is the percentage increase in total surface area?