Question 131406
He kept making the monthly payments of $20 and the $15 finance charge
Until $180 is paid off by the $20 payments alone, because the finance
charge does not count toward the $180.
Let {{{P}}}= his total payment for the skates
{{{P = 180 + (180/20)*15 - 15}}}
I subtracted $15 at the end because there is $0 balence left after
the last payment
{{{P = 180 + 9*15 - 15}}}
{{{P = 180 + 135 - 15}}}
{{{P = 300}}}
By paying the $250 regular price, he would have saved
{{{300 - 250 = 50}}} dollars