# Biology math help??

1. If a single bacterium starts dividing every 30 minutes , how long will it take for the Colony to reach 16 777216 bacteria. ???

Not really sure
2. 12 hours. I created my own method where 2^how many times it divides in a day. This divides every 30 mins, so twice an hour and 48 times a day. I plugged the numbers in, but got larger than your answer, so I halved it and got your answer with 2^24. Bit of trial and error.
3. (Original post by typicalvirgo;[url="tel:67994668")
67994668[/url]]12 hours. I created my own method where 2^how many times it divides in a day. This divides every 30 mins, so twice an hour and 48 times a day. I plugged the numbers in, but got larger than your answer, so I halved it and got your answer with 2^24. Bit of trial and error.
Did you just times the number, for example 24*16777216 ?
4. (Original post by Hazel99)
Did you just times the number, for example 24*16777216 ?
No you calculate how many times your cell divides a day. Your example divides every 30 mins, meaning twice an hour and 48 times a day.
60/30 = 2
2 x 24 = 48

If a cell divided every 20 mins, it would divide 3 times an hour, so 72 times a day.
60/20 = 3
3 x 24 = 72

To finish the calculation it's 2^what you just worked out. Adjust the number until it matches, keeping in mind what you did to the original.

Hope this helps.
5. (Original post by typicalvirgo;[url="tel:68003032")
68003032[/url]]No you calculate how many times your cell divides a day. Your example divides every 30 mins, meaning twice an hour and 48 times a day.
60/30 = 2
2 x 24 = 48

If a cell divided every 20 mins, it would divide 3 times an hour, so 72 times a day.
60/20 = 3
3 x 24 = 72

To finish the calculation it's 2^what you just worked out. Adjust the number until it matches, keeping in mind what you did to the original.

Hope this helps.
Thank you 😊
6. Just work out log to base 2 of 16777216 then multiply answer by 30 min (much quicker thn trial and error)

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