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 =

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