The probability that a patient will have a negative reaction to a certain medication is 0.03. The medication is administered to 75 patients. What is the expected number of negative reactions?

Hi Again Chris;

I love probability questions!

x=(75 patients)(0.03 negative patients/patient)

Let's cancel units where appropriate...

x=(75 patients)(0.03 negative patients/patients)

x=(75)(0.03 negative patients)

x=2.25 negative patients

Obviously, there is no such thing as 0.25 patients. So...

x=2 negative patients

I would like to stress, always make certain your units cancel appropriately. If these do not, you are working with the wrong equation.

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