According to a government commission, 70% of all the nation's households have vcrs. in a random sample of 15 households, what is the probability that have at least 13 vcrs? round to four decimal places.

Respuesta :

Number of trials, n = 15
Expected success, r  = 13
Probability of having a VCR, p = 70% = 0.7
Probability of not having a VCR, q = 1 - p = 0.3

According to the binomial distribution, the probability of 13 out of 15 households having a VCR is
₁₅C₁₃ p¹³ q¹⁵⁻¹³
= [15!/(13!2!)]*(0.7¹³)*(0.3²)
= 0.0916

Answer:  0.0916 (or 9.16%)