Answer:
165 minutes
Explanation:
We can break the numbers into prime numbers
15 = 3 * 5
33 = 3 * 11
55 = 5 * 11
The shortest time that must pass before they are all together again would be the least multiple that is divisible by all 3 number, which is
3 * 5 * 11 = 165
Hence after 165 minutes the 3 cars should all meet together again.
