Adam bought a $1,670 custom video game/sound system on a special no interest plan. he made
$100 down payment and agreed to pay the entire purchase off in 1 and half years. the minimum monthly
payment is $10. if he makes the minimum monthly payment up until the last payment, what will be
the amount of his last payment?

Hello!

if he bought it with no interest applied, then the last payment will be $1400

1670 - 100 = 1570

if he has to pay it off in 18 months (1 and a half years), and only pays $10 per month, that means he will pay off $170 before the last payment is due.

1570 - 170 = 1400

so his last payment will have to be $1400 to pay it off completely

I hope this helps, and have a nice day!