Quantitative Aptitude - Arithmetic Ability Questions

The average weight of 30 students in a class is 25 kgs. If the weight of the class teacher is added, the average weight increase by 2 kgs. The weight of the class teacher in kgs is

If 2cos2A - 1 = x, then the value of x is

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 options.

If the standard deviation of a population is 6.5, what would be the population variance?

Identify the odd one out from the following:

The simplified form of (x + 3)2 + (x - 1)2 is

If the areas of two similar triangle are in the ratio 5 : 7, then what is the ratio of the corresponding sides of these two triangles?

A solid sphere of diameter 17.5 cm is cut into two equal halves. What will be the increase (in cm2) in the total surface area?