A man can cross a downstream river by steamer in 40 minutes and same by boat in 1 hour. If the time of crossing Upstream…

A 6 × 6 grid is cut from an 8 × 8 chessboard. In how many ways can we put two identical coins, one on the bl…

If a distance of 50 m is covered in 1 minute, 90 m in 2 minutes and 130 m 3 minutes. Find the distance covered in 15<…

A train passes two persons walking in the same direction at a speed of 3 km/hr and 5 km/hr respectively in 10 seconds an…

From two places, 60 km apart, A and B start towards each other at the same time and meet each other after 6 hour. If A t…

The length of a train and that of a platform are equal. If with a speed of 90 km/hr the train crosses the platform in on…

One third of a certain journey is covered at the rate of 25 km/hr, one forth at the rate of 30 km/hr and the rest at 50 …

Each wheel of a car is making 5 revolutions per second. If the diameter of a wheel is 84 cm, then the speed of the car i…