Quantitative Aptitude - Arithmetic Ability Questions

Select the odd word/letters/number/number pair from the given alternatives.

If a - b = 2 and ab = 24, then what is the value of a3- b3?

What is the fourth proportional to 72, 168 and 150?

A vendor buys some bananas at the rate of 2 for Re 1 and sells at the rate of 10 for Rs 7. What will be the result?

If 5(4­-x) - ­4 < 3x - ­2 > 4x - 6; then the value of x is

If x + y = 13 and x2 + y2 = 89, then find xy is

If a + b = 3 and ab = -4, then what is the value of a3 + b3?

In a class there were 28 boys and some girls. In a test the mean score obtained by the boys was 12.5 while that obtained by the girls was 14.5. If the overall average was 13.1, what was the total number of students in the class?