Question 1146976
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The number of bacteria after t hours is<br>
{{{1*(1.04)^t}}}<br>
Solve the equation<br>
{{{(1.04)^t = 1200}}}<br>
To find the number of hours it takes for the number to reach 1200.  Then back up that many hours from 2:15pm to find when the experiment was started.<br>
Note the number of hours is equivalent to several days -- so I suspect the numbers given in the problem are not correct....