Question 1135102
.
<pre>
3*3 + 1 = 10 trains every 20 minutes from 6 am to 9 am inclusively

    PLUS

2*7 = 14 trains every 30 minutes from 9:30 am to 4 pm inclusively.



10 + 14 = 24 trains, in total.



<U>ANSWER</U>.  24 commuter trains, under given conditions.
</pre>

Solved.


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