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**fishcake** At 5.30 pm, train A is 15m away from the station, while train B is 0m away from the station. The distance of these two trains from the station in respect to the time (in hour) can be respresented as functions:

$\displaystyle f(t) = 60t + 15$ (for train A)

$\displaystyle g(t) = 80t$ (for train B)

The moment when train B catches up with train A is when both of the trains are at the same distance away from the station. That is, $\displaystyle f(t) = g(t)$. You'll end up with an equation:

$\displaystyle 60t + 15 = 80t$

Find the value of $\displaystyle t$ (which is time in hours) at that moment, and add it to the time (5.30 pm).