00:01
Okay, here i use the basic growth formula adapted to fit the compounding.
00:06
Pn is the end amount, p0 starting amount, 1 plus r over 100, r is the interest rate, power of n.
00:18
I take care with the r value here.
00:21
Now, end amount is 3 ,100, starting amount is 2 ,000, 1 plus, the rate is 3 ,000, 1 plus, the rate is 3 .1 ,000.
00:31
1 % per year i want per month as i'm compounding monthly so i divide that by 12 over 100 and n is number of months so i want to find the value of n first step divide both sides by 2 ,000 so i get 3100 divided by 2 ,000 equals then on a calculator let's work out 3 .1 divided by 12 divided by 100 and add on the 1 what i get here is 1 .0508 and then 3 repeating power of n.
01:30
Now on the left that becomes 31 over 20 and now i'll take logs of both sides.
01:42
I'll put log here and i'll put log over here as well.
01:56
Now, on the left end we have log of 31 over 20, and by the third law of logs, the n comes down in front, and log 1 .00258...