Question 195269
A cell divides into two identical copies every 4 minutes. How many cells will exist after 5 hours? Here is the answer, I was told I have a typo in it, cannot find it.

  	Growth Formula
A(t)=A<sub>o</sub>(2)^(t4) where t is the number of minutes after t=0

A(300)= 1*2^(300/4)
A(300)=2^(75)
A(300)= 3.77x10^22 cells

Thanks


At the beginning there is 1, or 2^0 cells.
At the instant the 1st four minutes is up, there will be 2, or 2^1 cells. 
At the instant the 2nd four minutes is up, there will be 4, or 2^2 cells. 
At the instant the 3rd four minutes is up, there will be 8, or 2^3 cells.
At the instant the 4th four minutes is up, there will be 16, or 2^4 cells.
At the instant the 5th four minutes is up, there will be 8, or 2^5 cells. 

Every hour consists of 15 four-minute periods, since 60 divided by 4 is 15.

So 5 hours consiste of 5x15 or 75 four-minute periods, therefore

At the instant the 5th four minutes is up, there will be 8, or 2^75 cells.

So the answer is 2^75 which is a 23-digit number.

So A(300)=2^(75)

would be the correct choice.  The 300 is because there are 300 minutes
in 5 hours.

Edwin</pre>