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# Calculating e coli cells in one colony watch

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1. Okay i got this questiob wrong and in really not sure why. It said that one e coli cell was allowed to grow and replicates every 20 mins. With an incubation time of 10 hrs how many cells would you find?
I did 10 times 60. Divided that by 20. I got 30 and did 2 to the power of 29 which gave me a massive answer which is apparently wrong. But I dont understand why. Help pls.
2. (Original post by err..)
Okay i got this questiob wrong and in really not sure why. It said that one e coli cell was allowed to grow and replicates every 20 mins. With an incubation time of 10 hrs how many cells would you find?
I did 10 times 60. Divided that by 20. I got 30 and did 2 to the power of 29 which gave me a massive answer which is apparently wrong. But I dont understand why. Help pls.
I'm not sure why you did 2^29, in 10 hours the population doubles 30 times.
I'm not sure why you did 2^29, in 10 hours the population doubles 30 times.
But it starts off as one cell so you cant do 1 to the power of 29. So i doubled he one and raised it to the power of 29? Your way is correct but I really dont understand why
4. (Original post by err..)
But it starts off as one cell so you cant do 1 to the power of 29. So i doubled he one and raised it to the power of 29? Your way is correct but I really dont understand why
It doubles 30 times ie 1 x 2 x 2 x 2 x 2 ... etc, or just 1 x 2^30
It doubles 30 times ie 1 x 2 x 2 x 2 x 2 ... etc, or just 1 x 2^30
Still confused but thanks anyway.
6. (Original post by err..)
Still confused but thanks anyway.
It doubles 30 times, that means it x2 30 times. so

1x2x2x2x2x2x2x2x2x2x2x2x2x2x2x2x 2x2x2x2x2x2x2x2x2x2x2x2x2x2=1x2^ 30

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