# Science:Math Exam Resources/Courses/MATH102/December 2012/Question B 05

MATH102 December 2012
Other MATH102 Exams

### Question B 05

In the Chernobyl reactor explosion, which occurred on April 26, 1986, substantial amounts of the isotope strontium-90 (90Sr) contaminated the area around the nuclear plant. 90Sr decays at a rate proportional to its quantity. 90Sr has a half-life of 29 years; that is, it takes 29 years for a quantity of 90Sr to decrease by half. What is the proportion of 90Sr originally released which remains on April 26, 2012?

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