Problem 1: About 50% of all persons age 3 and older wear glasses or contact lenses. For a randomly selected group of five people find the probability that:(adsbygoogle = window.adsbygoogle || []).push({});

a. exactly three wear glasses or contact lenses

b. at least one wears them

c. at most one wears them

For this problem I set n=5, p=.25, and q(1-p)=.75

For (a) I used y=3, I set up a combination of (5 choose 3) * ((.25)^3) * ((.75)^2)

For (b) and (c) I'm confused as to what I should choose for (y).

Problem 2: If 25% of 11-year old children have no decayed, missing, or filled (DMF) teeth, find the probability that in a sample of 20 children there will be:

a. exactly 3 with no DMF teeth

b. 3 or more with no DMF teeth

c. fewer than 3 with no DMF teeth

d. exactly 5 with no DMF teeth

I set n=20, p=.25, and q(1-p)=.75

I'm not sure if Im setting up these right or not.

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# Binomial Probability

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