Quantitative Aptitude - Arithmetic Ability Questions

The simple interest accrued on a sum of money at the end of four years is 1/5th of its principal. What is the rate of interest per annum?

Pinaki is 9 years younger than Bhaswati. Thirteen years hence Bhaswati will be 1.2 times as old as Pinaki. Find Pinaki's present age.

Ratio of A's age to B's age is 4:3. 'A' will be 26 years old after 6 years. The age of B now is

A uniformly moving train of length 480 m takes 3 minutes to completely cross a platform. If the same train, with the same speed crosses a pole completely in 30 sec, then the length of the platform is -

A, B and C together can complete a work in 25 days. If the ratio of efficiency of A, B and C is 15 : 10 : 6 respectively, then in how many days C alone can complete the same work?

If A, B and C together do a job in 4 days, A and C together do the job in 4.5 days and B and C together do the job in 12 days then in how many days can C alone do the job?

Prabodh has done 1/2 of a job in 30 days, Sapan completes the rest of the job in 45 days. In how many days can they together do the job?

In a class of 60 students there are 20 girls who scored an average of 40 marks in the test, what is the average marks of the boys if the class average is 60 marks?