Two boats, traveling at 5 and 10 kms per hour, head directly towards each other. They begin at a distance of 20 kms from each other. How far apart are they (in kms) one minute before they collide?
Correct Answer : C
If 9 engines consume 24 metric tonnes of coal, when each is working 8 hours a day; how much coal will be required for 8 engines, each running 13 hours a day, it being given that 3 engines of the former type consume as much as 4 engines of latter type.
The distances from A to B, B to C and C to D, are 12 kms. each. A man runs from A to B at a speed of X kms/hour. After reaching B, he rests for X hours and runs from B to C at double the previous speed. At C he rests for 2 X hours and runs from C to D at double his speed from B to C. He reaches D in 16 hrs after starting from A. Then a possible value of X is
Pipe A can fill in 20 minutes and Pipe B in 30 mins and Pipe C can empty the same in 40 mins.If all of them work together, find the time taken to fill the tank