If a driver drives at the rate of 32 km/h, he reaches his destinatin 7 minutes late. If the drives at the rate of 35km/h he reaches 4 minutes earlier. How far is his destination?

After covering a distance of 30 km with a uniform speed there is some defect in a train engine and, therefore, its speed is reduced to 4/5 of its original speed. Consequently, the train reaches its destination late by 45 minutes. Had it happened after covering 18 kilometres more, the train would have reached 9 minutes earlier. Find the speed of the train and the distance of journey.

A man would be 5 minutes late to reach his destination if he rides his bike at 30 km per hour.But he would be 10 minutes early if he rides at the speed of 40 km per hour.What is the distance of his destination from where he starts?

An airforce plane is ascending vertically at the rate of 100 (km)/h . If the radius of the earth is r km, how fast is the area of the earth, visible from the plane, increasing at 3 minutes after it started ascending?Given that the visible area A at height h is given by A=2pir^2h/(r+h)

A man has to walk a certain distance. He finds that if he walked 1/4 of a km an hour faster he will take 20 minutes less, but if he walks 1/2 km an hour slower he will take 52 minutes more. Find the distance and his rate of walking.

A man can swim with a speed of 4.0 km//h in still water. How long does he take to cross a river 1.0 km wide if the river flows steadily at 3.0 km//h and he makes his strokes normal to the river current? How far down the river does he go when he reaches the other bank ?