Question

Lodine-131 is a very useful radioactive isotope that is used to locate and treat cancerous tumors in the body and has a half life of 8 days. If a radiologist were to use 64 mg of this isotope, how much of it would still be left after 32 days?

Answer 1

Using an exponential function, it is found that 4 mg of the substance would still be left after 32 days.

What is an exponential function?

A decaying exponential function is modeled by:

$A(t) = A(0)(1 - r)^t$

In which:

• A(0) is the initial value.

• r is the decay rate, as a decimal.

In this problem, considering that the initial amount if of 64 mg, and we are working with half-lifes, the equation is given by:

$A(t) = 64(0.5)^t$

32 days is 32/8 = 4 half-lifes, hence the amount remaining in mg is given by:

$A(4) = 64(0.5)^4 = 4$

More can be learned about exponential functions at brainly.com/question/25537936