Given: George is at a location between his house and the concert hall. To reach the concert hall, he has two options, both taking the same amount of time: he can either walk directly there, or he can walk back to his house and then drive to the concert hall.
Asked: If George drives 12 times as fast as he walks, what is the ratio of George's distance from his house to his distance from the concert hall?
House-------------d1----------George -------------d2--------Concert Hall
Let the walking speed be v
Driving speed = 12v
Time taken to walk to concert hall = d2/v
Time taken to walk to home and then drive to concert hall = d1/v + (d1+d2)/12v
Since Time taken to walk to concert hall = Time taken to walk to home and then drive to concert hall
d2/v = d1/v + (d1+d2)/12v
1 = d1/d2 + (d1/d2 + 1)/12
Let d1/d2 = the ratio of George's distance from his house to his distance from the concert hall = k
12 = 12k + (k+1) = 13k + 1
k = 11/13
IMO C