Question 120632
A car and a bike set out at noon from the same point headed in the same direction. At 1:00 P.M., the car is 60 km ahead of the bike. Find how fast each travels, given that the car travels four times as fast as the bike.
:
Let s = speed of the bike
then
4s = speed of the car
:
The travel time for both is given as 1 hr (noon to 1PM):
:
write a distance equation Distance = time * speed
: 
Car dist - bike dist = 60 km
1(4s) - 1s = 60
4s - s = 60
3s = 60
s = {{{60/3}}}
s = 20 km/hr is the speed of the bike
then
4*20 = 80 km/hr is the speed of the car
:
:
Confirm solutions by finding distance traveled by each:
1*80 = 80 km
1*20 = 20 km
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dif = 60 km as given