Quantitative Aptitude - Arithmetic Ability Questions

In a class of 50 students there are 22 girls who scored an average of 35 marks in the test. What is the average marks of the boys if the class average is 42 marks?

If A's salary is 40% less than that of B, then how much percent is B's salary more than that of A?

Before a battle there were the ratio of captains to soldiers was 2 : 7. During the war 25 captains and 100 soldiers were martyred. The new ratio of captains to soldiers became 3 : 10. What is the number of soldiers after the war?

If Rs 7,800 is to be divided between A, B and C in the ratio 1/2 : 1/3 : 1/4, then how much share will B get (in Rs)?

What is the value of [12/(√5 + √3)] + [18/(√5 – √3)]?

You went to buy 3 articles worth Rs.500 each. However, as per the discount sale going on in the shop, you paid for two and got one free. What is the discount percentage in the deal?

To travel 612 km, an Express train takes 9 hours more than Rajdhani. If the speed of the Express train is doubled, it takes 3 hours less than Rajdhani. The speed (in km/hr) of Rajdhani is

A and B together can complete a task in 12 days. However, if A works alone, completes half the job and leaves and then B works alone and competes the rest of the work, it takes 25 days in all to complete the work. If B is more efficient than A, how many days would it have taken B to do the work by herself?