Carcass wrote:
If John had driven 1.5 times as fast on a certain trip, it would have taken him 6 hours. How many hours did it take him to drive that certain trip?
For this question, we're comparing a hypothetical trip with an actual trip.
Let
r = the travel speed of the actual trip.
So,
1.5r = the travel speed of the hypothetical trip.
Since John travels the
same distance for the actual trip and the hypothetical trip, we can start with the following word equation:
distance travelled during the ACTUAL trip = distance travelled during the HYPOTHETICAL tripLet
t = the travel time for the ACTUAL trip
Since distance = (rate)(time), we can plug our values into the word equation to get:
rt = (1.5r)(6)Expand:
rt = 9rDivide both sides of the equation by r to get:
t = 9Answer: 9