Answer:
8 : 36 am
Explanation:
we are trying to find:
train : 12
bus : 18
(the next time that 12 and 18 will both evenly go into a number/start at the same time will be the "lowest common multiple")
the lowest common multiple can actually be found fairly easily.
most people assume that finding the LCM (lowest common multiple) is a matter of guesswork - it's not
We can find the LCM by multiplying the absolute values of two numbers, and dividing by their GCD (greatest common divisor- the largest number that both can be evenly divided by).
12 and 18 share a GCD of 6.
So, we multiply 12 × 18 = 216
and divide by 6 216 / 6 = 36
The next time that the bus and train leave the station at the same time will be in 36 minutes--which will be 8 : 36 am.