pre calculus
posted by john .
if there are initial 2500 bacteria in a culture, and the number of bacteria double each hour, the number of bacteria after t hours cab n be found using the formula=N=2500(2^t).how long will it take the culture to grow to 75,000 bacteria.

75000=2500(2)^t
take the log of each side:
log(75000)=log(2500)+tlog(2)
log(30)=t log (2)
t= log(30)/log(2)
solve for t. Your calculator is your best friend on this. I get about five hours 
t=17.3538
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