Question 1005174
A bacteria colony grows continuously at an exponential rate. There are initially 1.6 million present. After 4 days, there are 6.6 million present.
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y = ab^x
a = 1.6 million
6.6 million = 1.6*b^4
b^4 = 4.125
b = 1.425
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a. What is an equation modeling the number of bacteria present after "d" days?
y = 1.6*1.425^d
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b. How many bacteria will be present after 9 days?
y = 1.6*1.425^9 = 38.77 million
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c. How long will it take the number of bacteria to reach 90 million?
90 = 1.6*1.425^x
1.425^x = 56.25
x = log(56.25)/log(1.425)
x = 11.38 days
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Cheers,
Stan H.
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