Question 902017
Difference in time for going and returning = 2 hours

let distance be x

t=d/r

time forward 
x/257

time return = x/277

time forward - time return = 2

x/257 - x/277 = 2

(277x-257x )/257*277 =2

20x = 257*277*2

x= 257*277*2/20
x=7118.9 miles

t=d/r
=7118.9/277

25.7 hours return trip