Question 840900
Day one : 50 miles = 50*(1)
Day two : 50 + 0.10(50)=50(1.1)=55
Day three : 55+0.1(55)=55(1.1)=50(1.1)(1.1)
{{{D=50(1.1)^(N-1)}}} where {{{N}}} is the days of riding
{{{D(60)=50(1.1)^(60-1)=50*1.1^59=50*276.8=13840}}}
On day 60, you're riding 13840 miles. Not really possible. 
At that point, you'd have ridden 151740 miles in 60 days. 
If you drive at 60mph for 60 days, 24 hours a day you only drive 86400 miles.