Carcass wrote:
From Aqua-Bella island, it is possible to reach Aqua-Marine island by either ferry A or ferry B. Ferry A sails 3 hours at 7 kilometers per hour, while ferry B takes a route that is three times longer. If ferry A is slower than ferry B by 2 kilometers per hour, how many hours longer is the journey of ferry B compared with the journey of ferry A ?
A. 4
B. 7
C. 8.6
D. 9.6
E. 12.6
Ferry A sails 3 hours at 7 kilometers per hour...Distance = (speed)(time)
So, ferry A's travel distance = (7)(3) =
21 kilometers
...while ferry B takes a route that is three times longer. So, ferry B's travel distance = (3)(
21) =
63 kilometers
If ferry A is slower than ferry B by 2 kilometers per hour, how many hours longer is the journey of ferry B compared with the journey of ferry A ?We already know that ferry A's speed is 7 kilometers per hour, which means ferry B's speed is
9 kilometers per hour.
Time = distance/speed
So ferry B's travel time =
63/
9 = 7 hours
So, ferry A's travel time = 3 hours, and ferry B's travel time = 7 hours, which means ferry B's travel time is 4 hours longer.
Answer: A