Question

The blue line arrives every 10 minutes the red line arrives every 8 minutes and the yellow line arrives every 12 minutes, how long until they arrive at the station at the same time

Answer 1

They all arrive at the station at the same time after 120 minutes.

Explanation:

For solving these types of question we use Least Common Multiples (L.C.M.).

Since for getting a common time they will meet, we interested in a multiplier.

Now, We will take L.C.M. of all the numbers:

10 = 2 × 5

8 = 2 × 2 × 2

12 = 2 × 2 × 3

∴ L.C.M. = 2 × 2 × 2 × 3 × 5 = 120 {taking smallest common multiples)

Thus, they all lines will meet after 120 minutes.