Quantitative Aptitude - Arithmetic Ability Questions

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

The simplest value of 38-212+20318-227+45 is

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

If 1p+1q = 1p+q, then the value of p3-q3

The circumference of a circle is equal to the perimeter of an equilateral triangle. If the radius of the circle is 7 cm what is the length of the side of the equilateral triangle?

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?

In a class of 60 students there are 33 girls. The average weight of these girls is 62 Kg and average weight of the full class is 66.5 kg. What is the average weight of the boys of the class?

What should be the average speed of a car to cover a distance of 189 km in 3.5 hours?