00:01
Find the monthly payment and the total interest that is paid.
00:04
So to find our monthly payment, our monthly payment is going to be our loan amount of 94 ,310 divided by 1 minus 1 plus our interest rate, which is 7 .8 % over 100.
00:23
So let's go ahead and, um, it's going to be our rate of our interest rate of 7 .8.
00:35
So 7 .8 % over 12 to the negative, we have 15 years, so 15 times 12 gives us 180.
00:46
So negative 180 divided by 7 .8 % over 12.
00:52
So 7 .8 % is just 0 .078.
00:57
So let's go ahead and plug that into a calculator.
01:00
We have 94 ,310 divided by, um, divided by our value of 1 minus 1 plus 0 .078 over 12 to the negative 180 power divided by 0 .078 over 12.
01:25
We get a monthly payment of 890 .4 dollars.
01:31
Now to find the total interest that's paid, that's our monthly payment of 890 times our number of months, 180 minus our loan amount, 94 ,310.
01:43
And now we plug that into a calculator.
01:44
So 890 times 180 minus 94 ,310.
01:49
We get interest paid of 65 ,890.
01:54
Now for b we're told, suppose a family decides to save an extra 100 ,000 dollars...