A can walk a certain distance in 10 days when he rests 9 hours a day. How long will he take to walk twice the distance, twice as fast and rest twice as long each day ?
A can walk a certain distance in 10 days when he rests 9 hours a day. How long will he take to walk twice the distance, twice as fast and rest twice as long each day ?
A4 days
B10 days
C15 days
D25 days
