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x has the value 1.

How would I calculate the accumulative value of x for a certain week, if x increases with 125% each week?

Fellow Stranger
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2 Answers2

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At the end of first week, $x$ becomes $1.25$

At the end of second week, $x$ becomes $1.25^2$

At the end of third week, $x$ becomes $1.25^3$

In general, at the end of $n^{th}$ week, $x$ becomes $1.25^n$

Adhvaitha
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  • Sorry for a dumb question, but is this possible to calculate with a simple calculator (like the one in an iPhone)? – Fellow Stranger Nov 18 '14 at 22:20
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    @Numbers On an actual pocket calculator (the ones that might be driven by a solar panel) you do it by typing 1.25, and then the multiplication button $n$ times. A calculator app should have an advanced panel. On that panel, look for a button with something like ^, x^y or $x^y$ written on it. – Arthur Nov 18 '14 at 22:23
  • Also, a $125%$ increase probably means that the factor is $2.25$ instead of $1.25$. – Arthur Nov 18 '14 at 22:30
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Hint: Calculate the amount that $x$ increases in week one, two, three and maybe four. Try to see a pattern in terms of an exponent that reflects which week you are in. Once you have that pattern, generalize the answer in terms of $n$.

graydad
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