SOLUTION: A jar has 4 amoebas in it to start. Amoebas split their cells in two (therefore doubling in size) once every minute. The jar will be completely filled in 10 minutes. How long would

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Question 963970: A jar has 4 amoebas in it to start. Amoebas split their cells in two (therefore doubling in size) once every minute. The jar will be completely filled in 10 minutes. How long would it take to fill the same sized jar if it had 8 amoebas in it to start? Make sure to explain your answer!
Answer by josgarithmetic(39838) About Me  (Show Source):
You can put this solution on YOUR website!
y=4%2A2%5Et, exponential growth model. t time in minutes; y population after any time t. Note, t=1 makes double the population from one minute before.

"Jar completely filled" when t=10. What y value is this?
y=4%2A2%5E10
y=4096.


What if 8 amoeba at t=0? How much time to reach y=1024 y=4096?
8%2A2%5Et=4096, -------------be sure you understand this step.

2%5Et=4096%2F8
2%5Et=%282%5E12%29%2F%282%5E3%29
2%5Et=2%5E9

The same base on both members, so the exponents must be equal.
highlight%28t=9%29