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.

If (x + y)/z = 2, then what is the value of [y/(y – z)] + [x/(x – z)]?

Simple interest on a sum of Rs 6800 for 18 months is Rs 2244. What is the rate (in percentage) of interest per annum?

In a triangle the length of the side opposite the angle which measures 30° is 9 cm, what is the length of the side opposite to the angle which measures 60°?

The radius of a hemisphere is 21 cm, what is its volume? (Take π = 22/7)

What must be the length (in cm) of the diagonal of a rectangle if its area and breadth are 120 sq.cm and 8 cm respectively ?

The base area of a right pyramid is 57 sq. units and height is 10 units. Then the volume of the pyramid is

In what ratio wheat costing Rs 17/kg mixed with another wheat costing Rs 12/kg to get a mixture costing Rs 13.5/ kg?