The probability that an electronic device produced by a company does not function properly is equal to 0.1. If 10 devices are bought, then the probability, to the nearest thousandth, that 7 devices function properly is  Pick.
A) 0.057  B) 0.478  C) 0.001  D) 0  E) None
Solution   Let q being the probability a device does not function properly and p = 1 - q = 0.9 the probability that a device functions properly. Since there are only two possible results, it is a binomial distribution. The P probability that 7 out of 10 devices function properly is given by   C(10,7)*0.9 7*0.1 3 , where C(10,7) is the number of ways that 7 items are selected from 10 and is given by   P = C(10,7) = 10! / (7!3!)   0.057 calculation of P gives   P = 0.057   0.057nswer 0.057
<result>A</result>
The probability that an electronic device produced by a company does not function properly is equal to 0.1. If 10 devices are bought, then the probability, to the nearest thousandth, that 7 devices function properly is