SOLUTION: Can you solve: A scientist notes the bacteria count in a petrie dish is 50. Two hours later, he notes the count has increased to 80. If this rate of growth continues, how much more

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Question 741431: Can you solve: A scientist notes the bacteria count in a petrie dish is 50. Two hours later, he notes the count has increased to 80. If this rate of growth continues, how much more time will it take for the bacteria count to reach 100? without logarithm?
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
A scientist notes the bacteria count in a petrie dish is 50.
Two hours later, he notes the count has increased to 80.
50^(2g) = 80
Find the growth rate
If this rate of growth continues, how much more time will it take for the bacteria count to reach 100? without logarithm?
:
Using the ratio of change to ratio of hrs
let t = time to reach 100
%28%2880-50%29%29%2F%28%28100-50%29%29 = 2%2Ft
30%2F50 = 2%2Ft
30t = 50*2
30t = 100
t = 100/30
t = 31%2F3 hrs
But it asks how much more time
31%2F3 - 2 = 11%2F3 hrs to go from 80 to 100 count