How many millicuries of technetium-99 should be given to a person who weighs 120 lbs?

Question

The recommended dosage of technetium-99 for use in imaging lungs is 20. μCi/kg of body weight. How many millicuries of technetium-99 should be given to a person who weighs 120 lbs? (1lb = 454 g)

Answer 1

120 lbs x 454 g/lb x 1 kg/1000 g x 20 uCi/kg x 1 mCi/1000 uCi = 1.0896 mCi = 1.1 mCi (2 sig. figs.)