D. none of these
Mary jogs 9 km at a speed of 6 km per hour. At what speed would she need to jog during the next 1.5 hours to have an average of 9 km per hour for the entire jogging session?
The length of the bridge which a train, 130 metres long and travelling at 45 km per hour, can cross in 30 seconds, is
Excluding stoppages, the speed of a bus is 54 kmph and including stoppages, it is 45 kmph. For how many minutes does the bus stop per hour?
The jogging track in a sports complex is 726 metres in circumference. Deepak and his wife start from the same point and walk in opposite directions at 4.5 km/hr and 3.75 km/hr respectively. They will meet for the first time in:
Sakshi can do a piece of work in 20 days. Tanya is 25% more efficient tha Sakshi. The number of days taken by Tanya to do the same piece of work is
A boat covers a distance of 30km downstream in 2 hour while it takes 6 hour to cover the same distance upstream. What is the speed of the boat in km/hr
A man’s speed with the current is 15 km/hr and the speed of the current is 2.5 km/hr The man’s speed against the current is?
A boy goes to his school form his house at a speed of 3 km/hr and returns at a speed of 2 km/hr. If he takes 5 hours in going and coming, the distance between his house and school is:
P and Q can complete a work in 20 days and 12 days respectively. P alone started the work and Q joined him after 4 days till the completion of the work. How long did the work last?
A thief steals a car and drives it at 15 km/hr. The theft has been discovered after one hour and the owner of the car sets off in another car at 25 km/hr. When will the owner overtake the thief from the starting point?