Challengeborough’s underground train network consists of six lines, , as shown. Wherever two lines meet there is a station which enables passengers to change lines. On each line, each train stops at every station. Jessica wants to travel from station to station . She does not want to use any line more than once, nor return to station after leaving it, nor leave station having reached it.
How many different routes, satisfying these conditions, can she choose?
Select one option, then click Submit.
9
36
41
81
720
Select an option, then submit.
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Senior Mathematical Challenge 2013 (2013)
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