Quantitative Aptitude - Arithmetic Ability Questions

A shopkeeper by selling 21 items earns a profit equal to the selling price of 1 item. What is his profit percentage?

If the measure of the interior angle of a regular polygon is 1800, then how many sides does it have?

0.09% of 25% of 1200 is equal to____________.

The quadratic equation 1+a2x2+2abx+b2-c2=0 has only one root. What is the value of c21+a2 ?

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?

To travel 708 km, an Express train takes 6 hours more than Rajdhani train. If however, the speed of the Express train is doubled, it takes 3 hours less than Rajdhani train. What is the speed of Rajdhani train?

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?

What is the average of first 19 odd numbers?