00:01
So we know that the compound interest formula is a equal to p has 1 plus r over n to the power.
00:12
Now we're told that a is $10 ,000, r is 0 .01, n is 20 years.
00:30
I mean, sorry, n is 12 since it's compounded monthly, and t is 20 years.
00:39
So now if we just plug all of this into our formula, you'll see that p is missing and that's what we're trying to solve for.
00:51
So 10 ,000 is equal to p times 1 .0 .01 over 12 to power 12 times 20.
01:11
So now we're just going to bring this whole thing down to this side to isolate p.
01:20
So you get p, let's get a 10 ,000 over 1 plus 0 .01 over 12, power of 12 times 20.
01:40
If you plug all of that directly to the calculator, we'll get 13, no, 1.
01:45
13, uh, 1 ,346 .62.
01:52
So that's how much would have had to be invested.
01:58
That's part a of the problem...