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

A vessel contain some litres of pure milk. If 25 litre of water is added to the vessel, then ratio between milk and water becomes 12:5, 17 litres of mixture is drawn from the vessel and 10 litre of water is added to the mixture. Find the new ratio between milk and water. 

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:

In a village, 70 % registered voters cast their votes in the election. Only two candidates (A and B) contested the election. A won the election by 400 votes. Had A received 12.5 % less votes, the result would have been tie. How many registered voters are there in the village? 

What should come place of the question mark(?) in the following number series?
17, 18 , 26, 53 , 117, ? , 458

What will come in place of the question mark (?) in each of the following series?

6 13 38 ? 532 2675 

In how many ways can a committee schedule three speakers for three different meetings if they are all available on any of five possible dates?