Question

A medical battery loses 5% of its power each week. How long will it take until only 20% of

its power remains.

Answer if you only know

Answer 1

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`20=100(0.95)^t`


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`0.2=0.95^t`


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`Log \ 0.2 = t \ log.95`


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`(log0.2)/(log.95) = t`


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`31.4 \ weeks = t`


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`Hence \ solved`