Math Equation...
- Thread starter shadow123
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shadow,
here's one
rule of 72.
1.02 ^ 36 = 2.0 (note 2 x 36 = 72)
1.03 ^ 24 = 2.0 (note 3 x 24 = 72)
1.04 ^ 18 = 2.0 (note 4 x 18 = 72)
1.06 ^ 12 = 2.0 (note 6 x 12 = 72)
1.08 ^ 9 = 2.0 (note 8 x 9 = 72)
1.09 ^ 8 = 2.0 (note 9 x 8 = 72)
1.12 ^ 6 = 2.0 (note 12 x 6 = 72)
36 years at 2% (compound) will double your money
24 years at 3% ditto etc etc
so
9 years at 8% (where 9 x 8 = 72) will double your money
here's one
rule of 72.
1.02 ^ 36 = 2.0 (note 2 x 36 = 72)
1.03 ^ 24 = 2.0 (note 3 x 24 = 72)
1.04 ^ 18 = 2.0 (note 4 x 18 = 72)
1.06 ^ 12 = 2.0 (note 6 x 12 = 72)
1.08 ^ 9 = 2.0 (note 8 x 9 = 72)
1.09 ^ 8 = 2.0 (note 9 x 8 = 72)
1.12 ^ 6 = 2.0 (note 12 x 6 = 72)
36 years at 2% (compound) will double your money
24 years at 3% ditto etc etc
so
9 years at 8% (where 9 x 8 = 72) will double your money
I guess just for "completeness" of sorts, we should add that the interest rate, i, is the effective interest rate which may or may not be the p.a. quoted.
eg for 8%pa compounding annually, i=0.08 and n=number of years (as above.)
compounding semiannually, i=0.04 and n=2xnumber of years
compounding quarterly, i=0.02 and n=4xnumber of years
etc etc
you've got the message
the rule of 72 is good but it's just an approximation.
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e = mc^2
Timmy
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LOL!
wayneL
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OK, I getting confused!
What does "^" signify in these equations? It seems to metamorphose its function throughout this thread.
Doh!
What does "^" signify in these equations? It seems to metamorphose its function throughout this thread.
Doh!
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next question rhen
is there a difference between 2 and 2.0 (in your line of business)
(there is in mine
)
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next question rhen
is there a difference between 2 and 2.0 (in your line of business)
(there is in mine
Only for very large values of 2 - now a mathermatician would appreciate that joke.
wayneL
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So is there a difference between ^ and x in your business?next question rhen
is there a difference between 2 and 2.0 (in your line of business)
(there is in mine
(There is in mine)
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So is there a difference between ^ and x in your business?
(There is in mine)
I'd be concerned if there wasn't a difference, in any situation.
wayneL
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santob and wayne,
me too (concerned etc)
then again there are such things as mistakes.
and wayne, I think you'll find you have made one in accusing me of getting "x" and "^" confused.
btw, here's that table
and the difference between 2 and 2.0 is the fact that you are accurate to 2 significant figures in the second case. (note that the approxmation is evident when you take it to three significant figures. )
btw, that rule of 72 also works for trades obviously.
i.e. between now and end of financial year, if you make a trade each week for 12 weeks that grows by 6% each (compounding), then you'll have doubled your money. Easy if you say it fast.
wayne said:
gee whiz wayne, I would have thought you'd double check before double posting.wayne said:
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wayneL
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PM me a list of bridges you've built; just so I know for if I ever come back to Oz.
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