Boat A covers 240 km downstream distance in river P in 8 hours and Boat B covers 88 km upstream distance in river Q in 4 hours. The ratio of the speed of boat A and B in still water is 11 : 13. If the sum of the speed of the stream of River P and River Q is 12 km/h, find the difference between the speed of the stream of rivers P and Q.

Ramesh covers 56 part of the total distance by bus and the remaining 36 km by car. What is the total distance of his journey?

A person covers a distance of L km in 12 hours. If he increases his speed by 10 m/s, he covers the same distance in 8 hours. Which of the following statements is/are correct? I. The value of L is 760 km. II. The original speed of the person is 72 km/h.