Quantitative Aptitude - Arithmetic Ability Questions

In the following question, four number pairs are given. The number on left side of (–) is related to the number on the right side of (–) with some Logic/Rule/Relation. Three are similar on basis of same Logic/Rule/Relation. Select the odd one out from the given alternatives.

If √(1 + cot2A) = x, then the value of x is

If a cone is divided into two parts by drawing a plane through the midpoints of its axis, then the ratio of the volume of the 2 parts of the cone is

Select the related word/letters/number from the given alternatives.
1 : 8 :: ? :64

Find the fraction which bears the same ratio to 1/27 that 3/7 does to 5/9 .

In the last financial year, a car company sold 41,800 cars . In this year, the target is to sell 51,300 cars . By what percent must the sale be increased ?

The sum of a non-zero number and its reciprocal is 2. What is the number?

What is the equation of the line perpendicular to the line 5x + 3y = 6 and having Y-intercept -3?