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Alex777 [14]
3 years ago
5

The amount of a sample remaining after t days is given by the equation p(t)=A(1/2)^t/h, where A is the initial amount of the sam

ple and h is the half-life, in days, of the substance. A sample contains 18% of its original amount of Radon-222. The half-life of Radon-222 is about 3.8 days. Which is the best estimate for the age of the sample?
Mathematics
2 answers:
svp [43]3 years ago
6 0

Answer:

  9.4 days

Step-by-step explanation:

Filling in the given numbers, we can solve for t:

  0.18 = 1·(1/2)^(t/3.8)

  log(0.18) = (t/3.8)log(1/2)

  t = 3.8·log(0.18)/log(0.50) ≈ 9.4 . . . . days

The best estimate of the age of the sample is 9.4 days.

hjlf3 years ago
4 0

Answer:

9.4 days

Step-by-step explanation:

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