Solving for X: A Challenging Math Problem with Exponential Growth Rates

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Hardest Math Problem EVAR!

Homework Statement



300 * 1,05x = 160 * 1.07x

Homework Equations



what is x?


The Attempt at a Solution



140 = 1,05x / 1.07x

i can solve this using a graphic calculator but i want to do it mathematically.
 
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Your combined form should be 300/140=1.07^x/1.05^x. Take the log (any base) of both sides. Do you see how the laws of logarithms log(a*b)=log(a)+lob(b) and log(a^x)=x*log(a) can make this the easiest linear equation EVAR!
 
Last edited:


is it 300/140 or 300/160?

thanks for the help.
 


(1.05/1.07)x = 160 / 300

got it muchos gracias.