Quantitative Aptitude - Arithmetic Ability Questions

The length of the diagonal and the breadth of a rectangle is 26 cm and 10 cm respectively. Calculate its area (in cm2).

A piece of work was finished by A, B and C together. A and B together finished 60% of the work and B and C together finished 70% of the work. Who among the three is most efficient?

The height of the equilateral triangle is 9 cm. What is the radius (in cm) of the circle circumscribing the three vertices?

The ratio of number of boys to the number of girls in a school of 432 pupils is 5 : 4. When some new boys and girls are admitted, the number of boys increase by 12 and the ratio of the boys to girls changes to 7 : 6. The number of new girls admitted is

Find the odd one out among the following.

If 3x + 5y + 7z = 49 and 9x + 8y + 21z = 126, then what is the value of y?

x and y are two numbers such that their mean proportion is 9 and third proportion is 243. What is the value of x and y?

If ab+ba = -1, then the value of a2b-b2a is