Please help with this word problem?

Question

A radioactive isotope, iron-52, used in the creation of medical images of bone marrow, has a half-life of 8.2 hours. If 8 microcuries are given to a patient, how many microcuries are left after 12 hours?

Answer 1

A(t) = amount left

 

t_1/2 = 8.2 hours

 

A(t) = A₀ (1/2)^t/8.2,

 

A₀ = initial amount

t = hours

 

A(12) = 8 (1/2)^12/8.2 ≅ 2.901 microcuries