A train travelling at 36 km/h crosses a pole in 25 seconds. How much time (in seconds) will it take to cross a bridge 350 m long?

On simplification of   $$ {(2.664)^2-(2.356)^2\over0.288}$$

When the price of an audio system was reduced by 20%, the sale increased by 80%. What was the net effect on the sale?

What is the compound interest on Rs. 48,000 for 2 years at 20% p.a., if interest is compounded annually?

The sum of the ages of a father and son is 45 years. Five years ago, the product of their ages was 34. The present ages of father and son are _______, respectively.

The bisector of ∠B in ΔABC meets AC at D. If AB=10 cm and BC=11 cm and AC=14 cm, then the length of AD is:

If an amount doubles automatically in 8 years, then what is the interest rate?

The average weight of 15 students of a class increases by 1.5 kg when a student of 40 kg is replaced by a new student. What is the weight (in kg) of the new student?