Question

A cell divides into two identical copies every 4 minutes. How many cells will exist after 5 hours?

Answer 1

Convert 5 hours to minutes first, and then divide by 4, and multiply by two.

Answer 2

Katy, not quite so simple.

there are 300 minutes in 5 hours, so there would be 300/4 or 75 splits

4 min -- 2 cells = 2^1 - 1st split
8 min -- 4 cells = 2^2 - 2nd split
12 min -- 8 cells = 2^3 - 3rd split
16 min -- 16 cells = 2^4 -4th split
20 min -- 32 cells = 2^5 - 5th split
.
.
60 min -- 32768 cells = 2^15 - 15th split
.
.
300 min = 3.7779 x 10^22 = 2^75 - 75th split

It has been estimated that there are approximately 6.33 x 10^22 grains of sand on this earth, you have quite some prolific cells there.

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