Question 978090

if Chris has ridden {{{64}}} miles of a bike course  the course is {{{80}}}
 miles long, he has ridden {{{x}}}% or {{{x/100}}}  miles of {{{80}}}
 miles 

so, {{{64=(x/100)80}}}

{{{64=(x/10)8}}}
{{{64=8x/10}}}
{{{64*10=8x}}}
{{{640/8=x}}}
{{{x=80}}}

your answer is:Chris has ridden {{{80}}}% of the course so far