Question

Three cyclists simultaneously start their movement from the same point at 7 am. Their routes take 10 minutes, 25 minutes and 15 minutes, respectively. When will be the first time that the three cyclists meet again at the starting point?

Answer 1

The 3 cyclists will meet at the starting point again after 150 minutes.

Explanation:

Since they start at the same point but then take different times to each route, then to find the first time they will each meet at the starting point, we have to find the lowest common multiple (LCM).

Let's use prime factorization to get it.

Prime factorization of 10 = 2 × 5

Prime factorization of 15 = 3 × 5

Prime factorization of 25 = 5 × 5

Thus,super set = 2, 3, 5, 5

Thus,LCM = 2 × 3 × 5 × 5 = 150

Thus,the 3 cyclists will meet at the starting point again after 150 minutes.