Quantitative Aptitude - Arithmetic Ability Questions

If a2+b2=80 and ab = 32, then calculate the value of a-b/a+b.

In a school , 391 boys and 323 girls have been divided into the largest possible equal classes , so that each class of boys numbers the same as each class of girls . What is the number of classes ?

The mode and median of the data 8, 6, 8, 7, 8, 6, 8, 7, 6 is

The sum of the ages of father and a son presently is 70 years. After 10 years, the son's age is exactly half that of the father. What are their ages now?

A vendor buys apples at the rate of 21 for Rs 7 and sells at the rate of 5 for Rs 2. What will be the result?

A sphere of radius 21 cm is cut into 8 identical parts by 3 cuts (1 cut along each axis). What will be the total surface area (in cm2) of each part?

Two cars A and B travel from one city to another city, at speeds of 60 km/hr and 108 km/hr respectively. If car B takes 2 hours lesser time than car A for the journey, then what is the distance (in km) between the two cities?

A rice trader buys 8 quintals of rice for Rs 3,600. 10% rice is lost in transportation. At what rate should he sell to earn 15% profit?