Quantitative Aptitude - Arithmetic Ability Questions

The average revenues of 9 consecutive years of a company is Rs 76 lakhs. If the average of first 5 years is Rs 71 lakhs and that of last 5 years is Rs 83 lakhs, find the revenue for the 5th year.

A tyre is sold at three successive discounts of 20%,30%, and 20%. What is the net discount (in percentage)

The ratio of number of boys and girls in a class is 2 : 3. The average weight of boys and girls in the class is 18 kg and 21 kg respectively. What is the average weight (in kgs) of all the boys and girls together?

A and B have to type a book together containing 120 pages. A takes 9 hrs to type 36 pages and B takes 5 hrs to type 40 pages. A typed first 60 pages alone and the last 60 pages were typed by A and B together. How much time (in hours) will be taken to type the complete book?

If a wholesaler, sells a tin of coffee at Rs 528 he faces a loss of 12%. Now if he decides to sell it at Rs 636, what will be the profit (in %)?

The standard deviation of the set {10, 11, 9, 11, 9} is

P and Q are two alloys which are prepared by mixing tin and lead in the ratio of 12 : 5 and 4 : 3 respectively. If equal quantities of alloys are melted to form athird alloy R, then what is the ratio of tin and lead in alloy R?

Ravi invested Rs.P in a scheme A offering simple interest at 10% p.a. for two years. He invested the whole amount he received from scheme A, in another scheme (B) offering simple interest at 12% p.a. for five years. If the difference between the interests earned from schemes A and B was Rs. 13,00/, what is the value of P ?