Question 117398
If {{{t}}}hrs is the traveling time for the 2nd portion, 
{{{t + 1}}}hrs is the time for the 1st portion
{{{r = d/t}}}
{{{r[1] = r[2]}}}
{{{560/(t+1) = 480/t}}}
{{{560t = 480(t+1)}}}
{{{560t = 480t + 480}}}
{{{80t = 480}}}
{{{t = 6}}}hrs answer
check answer
{{{560/(t+1) = 480/t}}}
{{{560/7 = 480/6}}}
{{{80 = 80}}}
OK