Question 667579: Hoi Ching drives to work in 35 minutes. If she increases her average speed by 5km/h, she saves five minutes. How far from work does she live?
I can't seem to get the conversion between 5km/h to km/minute right, or to figure out the answer, since the distance is the same in both cases. Thanks for the help!
Answer by stanbon(75887)   (Show Source):
You can put this solution on YOUR website! Hoi Ching drives to work in 35 minutes. If she increases her average speed by 5km/h, she saves five minutes. How far from work does she live?
------
Original DATA:
time = 35/60 = 7/12 hr ; distance = x km ; rate = x/(7/12) = (12/7)x km/hr
---------
New DATA:
time = 30/60 = 1/2 hr ; distance = x km ; rate x/(1/2) = 2x km/hr
------
Equation:
2x - (12/7)x = 5 km/hr
----
(2/7)x = 5 km/hr
x = 5(7/2) = 35/2 = 17.5 km (distance to work)
=========================
Cheers,
Stan H.
=========================
|
|
|
