The distance traveled by Sarah equals the distance traveled by Evelyn, i.e.
60[x+(1/4)] = 78x where x is the time Evelyn traveled.
Remember 15 min = (1/4) hr and the rates are given in mph.
Once you solve the equation for x, then 78x is the distance traveled.
Can't solve the equation? OK.
Expand the left side: 60x + 15 = 78x
18x=15
You solve it from here.
P.S.
I guess you wouldn't mind if I wrote my answer as sloppily as you wrote your question!