This Focus takes the pattern developed in Focus J and generalized it for any situation.
The following reasoning applies:
This function is widely used to analyze binomial experiments. Graphing calculators and spreadsheets have built in functions for determining probabilities in binomial experiments.
A survey of university of students indicated 75% of the students preferred coffee over tea. If a random sample of 25 students is taken one month later, what is the probability that 20 of them prefer coffee?
There are 25C20 ways of selecting 20 students out of 25
For each student we have the following probabilities:
By the theoretical model, the overall probability will be
You should now be ready to complete the assigned work on this lesson.
Check Your Understanding p.349 - 350. Complete 12 to 20 inclusive
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