2. Various radioactive substances are used in medical tests. a. lodine-131 is used in thyroid tests. A 20-mg sample decays to 16.85 mg in 48 hours. What is the half-life of iodine-131, rounded to the nearest hour? b. Strontium-87 is used in some bone tests. After 1 hour, a 100-mg sample decays to 78.1 mg. Determine the half-life of strontium-87, rounded to the nearest tenth of an hour. c. A different radioactive substance has an initial mass of 50 mg and a half-life of 10 hours. How much of the substance will remain after 30 hours? Provide your answer to the nearest hundredth of a milligram.

2. Various radioactive substances are used in medical tests. a. lodine-131 is used in thyroid tests. A 20-mg sample decays to 16.85 mg in 48 hours. What is the half-life of iodine-131, rounded to the nearest hour? b. Strontium-87 is used in some bone tests. After 1 hour, a 100-mg sample decays to 78.1 mg. Determine the half-life of strontium-87, rounded to the nearest tenth of an hour. c. A different radioactive substance has an initial mass of 50 mg and a half-life of 10 hours. How much of the substance will remain after 30 hours? Provide your answer to the nearest hundredth of a milligram.

College Algebra

7th Edition

ISBN:9781305115545

Author:James Stewart, Lothar Redlin, Saleem Watson

Publisher:James Stewart, Lothar Redlin, Saleem Watson

Chapter4: Exponential And Logarithmic Functions

Section: Chapter Questions

Problem 13CC

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