It is known that 75% of a radionuclide decays away in 12 hours.If starting with 10 mCi, how much will be left after 6 hours?

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Calculations in nuclear medicine often involve expressing a mathematical concept as a ratio.The equation generally contains several numbers and one unknown value; here the unknown value is (x).The object is to solve for the unknown value by rearranging the terms in the equation.In this situation, the half-life of the material is t hours.Start with 10 mCi.After t hours, there is 5 mCi left.After another t hours, there is 2.5 mCi left.Starting with 10 mCi, after 2t hours, there is 2.5 mCi left, which is only 25% of the initial quantity, and so 75% decayed away.It is given that 75% decays away in 12 hours.So 2t = 12 hours and t = 6 hours.With a half-life of 6 hours, starting with 10 mCi, there would be 5 mCi left after 6 hours.

It Is Known That 75% of a Radionuclide Decays Away