Question

The probability that a college student uses Twitter for social networking is 0.92 if 9 students are chosen at random use the binomial probability formula to find the probability that more than 7 use Twitter

Answer 1

Answer:

0.8417

Step-by-step explanation:

The probability that a college student uses Twitter for social networking is $p=0.92,$ then the probability that a college student does not use Twitter for social networking is $q=1-p=1-0.92=0.08.$

9 students are chosen at random.

Use the binomial probability formula to find the probability that 8 use Twitter:

$C^9_8p^8q^{9-8}=9\cdot (0.92)^8\cdot (0.08)^1\approx 0.3695$

Use the binomial probability formula to find the probability that 9 use Twitter:

$C^9_9p^9q^{9-9}=1\cdot (0.92)^9\cdot (0.08)^0\approx 0.4722$

The probability that more than 7 students use Twitter is

$0.3695+0.4722=0.8417$