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Course: Staging content lifeboat > Unit 9

Lesson 7: Exponentials & logarithms
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Staging content lifeboat
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Exponentials & logarithms
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GRAVEYARD Algebra 2: Exponential and logarithmic functions

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Problem

Every chemical element goes through natural exponential decay, which means that over time its atoms fall apart and form other types of elements. Suppose we have a sample of the isotope Beryllium-11. The amount, B, of Beryllium-11 (in grams) left in the sample after t seconds can be modeled by the following function:
B(t)=300⋅2−t29
How long will it take the sample to get to 6 grams? Round your answer, if necessary, to 2 decimal places.
  • Your answer should be
  • an integer, like 6
  • an exact decimal, like 0.75
  • a simplified proper fraction, like 3/5
  • a simplified improper fraction, like 7/4
  • a mixed number, like 1 3/4
seconds