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Course: Algebra 2 > Unit 8

Lesson 6: Solving exponential models
Math
Algebra 2
Logarithms
Solving exponential models
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Exponential model word problems

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Problem

A culture of bacteria starts with 50 bacteria and increases exponentially.
The relationship between B, the number of bacteria in the culture, and d, the elapsed time, in days, is modeled by the following equation.
B=50⋅10d2
In how many days will the number of bacteria in the culture reach 800,000?
Give an exact answer expressed as a base-ten logarithm.
days