Monday

September 22, 2014

September 22, 2014

Posted by **Monica** on Monday, June 13, 2011 at 10:40pm.

- math/algebra -
**Reiny**, Monday, June 13, 2011 at 10:47pm30 = 40e^10k

.75 = e^10k

10k = ln.75

k = ln.75/10 = -.028768

then

1/2 = e^-.028768t

- .028768t = ln .5

t = ln .5/-.028768 = 24.09

the half-life is appr. 24.1 hours

**Answer this Question**

**Related Questions**

Pre Calculus - Exponential Growth and Decay Find the half-life of a radioactive ...

Algebra 2 help... - A half life of a certain radioactive is 36 days. An initial ...

chemistry - If there are 80 milligrams of a radioactive element decays to 10 ...

Pre Calculus - Exponential growth and decay find the half life of a radioactive ...

physics - A building has become accidentally contaminated with radioactivity. ...

Math - D.E.Q. - The half-life of a radioactive isotope is the amount of time it ...

calculus - The rate at which an amount of a radioactive substance decays is ...

linear/exponential - This question involves the half-life formula. In this ...

chemistry - Write a partial decay series for Po-214 undergoing the following ...

Math - A radioactive substance decays according to the formula Q(t) = Q0e−...