Quantitative Aptitude - Arithmetic Ability Questions

If X + 2Y = 27 and X - 2Y = -1, find the value of Y.

If the standard deviation of a population is 7, what would be the population variance?

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.

What is the square root of 5041?

Two circles with centres P and Q touch each other externally. A straight line drawn through the point of contact intersects the circle with centre P at A and the circle with centre Q at B. Then, which of the following is true?

What is the slope of the line parallel to the line passing through the points (5, -1) and (4, -4)?

Which pair is not similar to the other three?

The angles of elevation of the top of a tower 72 metre high from the top and bottom of a building are 30° and 60° respectively. What is the height (in metres) of building?