College algebra

posted by .

The radioactive element has a half-life of about 28 years and sometimes contaminates the soil. After 47 years, what percentage of a sample of the elements remain?

  • College algebra -

    fraction remain = (1/2)^n where n is the number of half life

    half life = p/n where p is the period of decaying i.e. 47 years

    so, first find n (number of half life using the half life equation and then find the fraction remain. convert this fraction to %

    hope that helps

Respond to this Question

First Name
School Subject
Your Answer

Similar Questions

  1. Chemistry

    Which radioactive sample would contain the greatest remaining mass of the radioactive isotope after 10 years?
  2. calculus

    The rate at which an amount of a radioactive substance decays is modeled by the differential equation dA/dt = kA, where A is the mass in grams, t is the time in years, and k is a constant. Answer the following. a) If a 100-gram sample …
  3. College Algebra

    The half-life of a radioactive material is about 34.6 years. How much of a 1-gram sample of the material is left after 30 years?
  4. Science

    What can scientists learn from the rate at which radioactive elements decay?
  5. Pre-Calc

    Tritium, a radioactive isotope of hydrogen, has a half-life of 12.4 years. Of an initial sample of 69 grams, how much will remain after 75 years?
  6. College algerba

    The​ half-life of a certain radioactive element is about 1500 years. After 2800 ​years, what percentage P of a sample of this element​ remains?
  7. College algebra

    If 70% of a radioactive element remains radioactive after 400 million years , then what percent remains radioactive after 600 million years?
  8. Science

    An element has a half-life of 30 years. If 1.0 mg of this element decays over a period of 90 years, how many mg of this element would remain?
  9. math

    An element has a half-life of 30 years. If 1.0 mg of this element decays over a period of 90 years, how many mg of this element would remain?
  10. Math

    The element strontium-90 is radioactive. The percent of strontium -90, A(t), left in a sample can be modelled by the half-life function A(t) = A0 (1/2)^t/29, where t represents the time, in years, after the initial time, and A0 represents …

More Similar Questions