Question

Two race cars are speeding around the racetrack at different speeds. One goes around the track in 2 minutes; the other goes around the track in 11/2 minutes. How often does the faster car pass the slower car?

Answer 1

6 minutes is the answer.

Explanation:

One goes around the track in 2 minutes.

The other goes around the track in
`1(1)/(2)` or 1.5 minutes

WE will find the least common multiple of 2 and 1.5.

The LCM of 2 and 1.5 is 6.

That means in every 6 minutes, both the cars are at the same point.

We have to tell how often does the faster car pass the slower car. The answer is in 6 minutes.

Answer 2

one car takes 2 minutes for once around
so in 1 minute it does a 1/2 around
.
second car takes 1 1/2 minutes for once around ( 1 1/2 = 3/2)
so in 1 minute it does 2/3 round

every minute the second car gains 2/3 -1/2 of the round

2/3 = 4/6, 1/2 = 3/6

4/6 - 3/6 = 1/6 of the track per minute

so every 6 minutes the faster car overtakes the slower car.