An article is sold at a profit of 20% of its cost price. If cost price and selling price reduces by Rs 10 and Rs. 5 respectively, then the percentage profit increased to 30%. Find the cost price?

Distance between A and B is 1200 km. If they start moving towards each other at same time, they will meet in 24 hrs. If A starts 10 hrs after B, then they will meet in 20 hrs. What are their respective speeds?

A sum of Rs. 6400 amounts to Rs. 6724 at 10% p.a. compounded quarterly. Find the time period.

A piece of wire when bent to form a circle will have a radius of 84 cm. If the wire is bent to form a square, the length of a side of the square is

The sum of two positive numbers is 20% of the sum of their squares and 25% of the difference of their squares. If the numbers are x and y then, is equal to

In two types of brass ratio of copper and zinc are 8: 3 and 15: 7 respectively. The ratio in which these two types of brass should be mixed, so that the ratio of copper and zinc in this new type of brass become 5: 2 is 

The sum of the digits of a two digit number is 15. When 9 is subtracted from the given number then its digits interchanged. What will be the required original number?

There are 80 students in a class out of these 15% are girls. The monthly fee of each girl is Rs.350 and monthly fee of each boy is 38% more than each girl. What is the total fee of girls and boys in the class?