Critical Reasoning (CR) | Re: The city of Workney, in raising bus fares from $1.00 to $1.25, propose

GMATNinja ,KarishmaB ,chetan2u

If option (E) was written as:

Fewerpoor riders would regularly purchase 18 fare tokens at once than would purchase only 9 fare tokens atonce

then, would option (E) becomerequired ornecessary for the argument to hold? I think that it would become an assumption because it would indicate that $20 outlay has become prohibitive for 'poor riders' and hence lesser no. of them are buying 18 tokens instead of 9tokens.