In a large metropolitan area, past records revealed that 30% of all the high school graduates go to college. from 20 graduates selected at random (n=20), what is the probability that exactly 8 will go to college?
Question
Answer:
The probability is 0.1144.Using binomial probability, we have:
[tex]_nC_r\times(p)^r\times(1-p)^{n-r} \\ \\_{20}C_8\times (0.3)^8 \times(1-0.3)^{20-8} \\ \\ \frac{20!}{8!12!}\times (0.3)^8 \times (0.7)^{12} \\ \\=0.1144[/tex]
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