Among a student group 49% use Google Chrome, 20% Internet Explorer, 10% Firefox, 5% Mozilla, and the latter use Safari. What is the probability that you need to pick 7 students to find 2 students using Google Chrome? Report answer to 3 decimals.

Question
Decimals
asked 2021-02-01
Among a student group 49% use Google Chrome, 20% Internet Explorer, 10% Firefox, 5% Mozilla, and the latter use Safari. What is the probability that you need to pick 7 students to find 2 students using Google Chrome? Report answer to 3 decimals.

Answers (1)

2021-02-02
Step 1
Probability of students using Google chrome \(\displaystyle={0.49}\)
Probability of students using other browsers \(\displaystyle={0.51}\)
Step 2
Probability that there is exactly two students using google chrome in a sample of 7 is given by
\(\displaystyle{P}={\left({{c}_{{2}}^{{7}}}\right)}.\cdot{\left({0.49}\right)}^{2}{\left({0.51}\right)}^{7}\)
\(\displaystyle{21}\cdot{0.2401}\cdot{0.034503}\)
\(\displaystyle{0.173965}\)
Thus, \(\displaystyle{p}={0.173965}\)
0

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