Question

Iodine‑125 (I125) is used to treat, among other things, brain tumors and prostate cancer. It decays by gamma decay with a half‑life of 54.90 days. Patients who fly soon after receiving I125 implants are given medical statements from the hospital verifying such treatment because their radiation could set off radiation detectors at airports.

If the initial decay rate (or activity) was 522 μCi, what will the rate be after 389.0 days?

decay rate:

How many months after the treatment will the decay rate be reduced to 16.5% of the original value? Assume months of 30 days.

months:

Answer 1