## Time at which price doubles in inflation.

anybody knows how to calculate the period which a commodity which faces inflation takes to double it's price, without knowing anything except the rate of inflation? You must give a very shortcut method.
Thanks.

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 If X is the rate of inflation - 100/x
 Thanks.

## Time at which price doubles in inflation.

 Quote by Bignose If X is the rate of inflation - 100/x
Actually, a much better approximation is the "rule of 72", which is that the number of years to double at an annual growth rate of x% is 72/x. This is because (1+p)^n ~ e^(np), and ln(2) = .69. A slight correction makes it 72 instead of 69. Try it. You'll find that (1+p)^(72/p) ~=2.0 for a wide range of p.

 Quote by phyzguy Actually, a much better approximation is the "rule of 72", which is that the number of years to double at an annual growth rate of x% is 72/x. This is because (1+p)^n ~ e^(np), and ln(2) = .69. A slight correction makes it 72 instead of 69. Try it. You'll find that (1+p)^(72/p) ~=2.0 for a wide range of p.
At last!!!!!!
I was waiting for someone who told me this rule! I wanted to know if this was familiar to all. Cheeeerup!!

 Is inflation compounded though? my dollar stays a dollar year to year if I hold on to it. If I take 2% off and its... I guess it makes sense to compound an inflation rate. Stupid trick question.

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 Quote by PhysicoRaj At last!!!!!! I was waiting for someone who told me this rule! I wanted to know if this was familiar to all. Cheeeerup!!
Indirection is sleazy. If you want to know something on this forum, just ask.