Two pipes P and Q can fill a cistern in 36 and 48 minutes respectively. Both pipes are opened together, after how many minutes should Q be turned off,so that the cistern be fill in 24 minutes?

Two friends A and B invest in a business in partnership. B borrows 20% of A’s salary, combines it with 60% of his salary and invests with A, who puts all of his remaining salary. One year later the ratio of profit of A and B is 5 : 3 respectively and B returns Rs. 21000 to A which he borrowed from him. What is the difference between salary of A and B?

In the given figure, AB‖CD, find the value of x:

Mohan, a shopkeeper, bought a shirt of list price ₹225 at a discount of 20%. If he wants a profit of 30% then he should sell the shirt for:

The average age of x and y is 18 years. If z is equal to 9 years the average of x, y and z is -

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