Quantitative Aptitude - Arithmetic Ability Questions

A, B and C can together do a job in 9 days. C alone can do the job in 36 days. In how many days can A and B do 50% of the job working together?

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.

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?

P and Q can do a project in 150 and 100 days respectively. In how many days can they complete 60% of the project if they work together?

From a container of milk, 5 litres of milk is replaced with 5 litres of water. This process is repeated again. Thus in two attempts the ratio of milk and water became 81 : 19. The initial amount of milk in the container was

If a+b=2c then the value of aa-c+cb-c is equal to (where a≠b≠c)

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?