Slow coach

How many of this company's coaches travelling in the opposite direction does the 10 am coach from Alphaton pass before reaching Betaville?

Problem

 

A coach company runs a service that connects two towns, Alphaton (A) and Betaville (B), which are $90$ miles apart.

 

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Slow Coach
 

The timetable below gives details of coaches travelling from A to B:

 

A depart 0600 0620 0640 0700 0720 0740 and at the same minutes past each hour until ... 2100 2120 2140 2200
B arrive 0730 0750 0810 0830 0850 0910 2230 2250 2310 2330
Coaches going from B to A leave at the same times:
B depart 0600 0620 0640 0700 0720 0740 and at the same minutes past each hour until ... 2100 2120 2140 2200
A

arrive
0730 0750 0810 0830 0850 0910 2230 2250 2310 2330

 

 

How many of this company's coaches travelling in the opposite direction does the $10$ am coach from A pass before reaching B?

 

Image
Slow Coach