The correct answer is d) 12.5%.
To calculate the percentage of technetium-99m left in the patient's body after 12 hours, divide the time elapsed by the half-life and raise it to the power of the number of half-lives.
In this case, 12 hours is equal to 2 half-lives (12/6 = 2).
Using the formula:
Percentage remaining = (1/2)^(number of half-lives) * 100
Plug in the values:
Percentage remaining = (1/2)^2 * 100
Percentage remaining = (1/4) * 100
Percentage remaining = 25%
Therefore, about 25% of the technetium-99m will be left in the patient's body 12 hours later.
Technetium-99m is a radioactive isotope commonly used in medicine as a radioactive tracer. A radioactive tracer is an isotope injected into the body to help create images for diagnosis of health problems. Technetium-99m has a half-life of 6 hours. If a patient receives a dose of technetium-99m one morning, about what percentage of the technetium-99m will be left in the patient's body 12 hours later?
a
6.25%
b
93.8%
c
25.0%
d
12.5%
1 answer
1 answer