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sarae85
Jun 20, 2009, 12:58 PM
I have this question that is bugging me and I am not very good at math or distance math so I want to see if I CAN GET SOME HELP.

A businessman drives from Washington D.C to Boston, a distance of 442, then makes a return trip. On the way to Boston, he drives 65 miles per hour, taking a 1 hour rest stop during the drive. After finishing his business in Boston, he makes the return trip driving at 60 miles per hour and takes a 45 minute rest stop halfway through the trip.
Which leg of the journey, Washington D.C. to Boston, or Boston to Washington D.C, takes the longer time?

Perito
Jun 20, 2009, 01:54 PM
A businessman drives from Washington D.C to Boston, a distance of 442, then makes a return trip. On the way to Boston, he drives 65 miles per hour, taking a 1 hour rest stop during the drive. After finishing his business in Boston, he makes the return trip driving at 60 miles per hour and takes a 45 minute rest stop halfway through the trip.
Which leg of the journey, Washington D.C. to Boston, or Boston to Washington D.C, takes the longer time?


Distance = rate x time

Outbound trip:
T1 = driving time outbound trip
T2 = total time outbound trip

442 miles = 65 miles/hr x T1
solve for T1; T1 = 442/65 = 6.8 driving time hours

T2 = T1 + 1 hour = 7.8 hours total (Washington to Boston)


Inbound trip:
T3 = driving time on return trip
T4 = total time on return trip

442 miles = 60 miles/hour x T3
Solve for T3; T3 = 442 / 60 hours ≈ 7.4 hours

T4 = T3 + 3/4 hour ≈ 8.1 total hours (Boston to Washington)

Which took longer? You can figure that out.