One painter can paint a wall in 30 minutes, another painter needs 15 minutes for the same size wall. How long will they take to paint the wall working together?
They can do this in 10 min
A painter needed 3 days to paint a room.
How long would it take him, working at the same rate, to paint a room twice as long and twice as wide?
A tap can fill a tank in 30 minutes, another tap can fill it in 1.5 hours.
If both the taps are opened at 11.40 am.
At what time will the tank be filled?