Question 1187573
.
the half life of caffeine in a child's system when a child eats or drinks something with caffeine in it is 2.5 h. 
How much caffeine would remain in a child's body if the child ate a chocolate bar with 20 mg of caffeine 8 hours before?
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<pre>
To make it simple


    8 hours = {{{8/2.5}}} = 3.2  of the half-life time periods of the caffeine.


THEREFORE,  20 mg of the caffeine  will disintegrate to  {{{20*(1/2)^3.2}}} = 2.18 mg of caffeine in 8 hours.    <U>ANSWER</U>
</pre>

Solved and explained &nbsp;(as simple as possible).


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&nbsp;&nbsp;&nbsp;&nbsp;- <A HREF=https://www.algebra.com/algebra/homework/logarithm/Population-growth-problems.lesson>Population growth problems</A> 

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&nbsp;&nbsp;&nbsp;&nbsp;- <A HREF=https://www.algebra.com/algebra/homework/logarithm/A-medication-decay-in-a-human%27s-body.lesson>A medication decay in a human's body</A> 

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Also, &nbsp;you have this free of charge online textbook in ALGEBRA-I in this site

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The referred lessons are the part of this online textbook under the topic "<U>Logarithms</U>".



Save the link to this online textbook together with its description


Free of charge online textbook in ALGEBRA-I
https://www.algebra.com/algebra/homework/quadratic/lessons/ALGEBRA-I-YOUR-ONLINE-TEXTBOOK.lesson


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