Rachel rents three DVDs from Watch Flicks and two DVDs from Bluechest. The probability that a DVD is faulty is 4% for Watchflix and 5% for Bluechest. All DVD rentals being faulty or otherwise are independent of each other. Calculate the probability that exactly two DVDs rented by Rachel are faulty.

Pr( Exactly 2 are faulty) = 0.017

Step-by-step explanation:

Probability that a Watchflix DVD is faulty = 4% = 0.04

Probability that a Bluechest DVD is faulty = 5% 0.05

Probability(Exactly 2 DVD are faulty) = Pr(the two faulty DVDs are from watchflix) + Pr(the two faulty DVDs are from Bluechest) + Pr(1 is faulty from Watchflix and the other from Bluechest)

Binomial distribution is given by:

Pr(the two faulty DVDs are from watchflix) =

= 0.0042

Pr(the two faulty DVDs are from Bluechest) = = 0.0022

Pr(1 is from Bluechest, 1 is from Watchflix) = = 0.01051

Pr( Exactly 2 are faulty) = 0.001386 + 0.0022 + 0.01051

Pr( Exactly 2 are faulty) = 0.0169 = 0.017

good luck on your studies! : )

david edward.

2.2°  

step-by-step explanation:

let θ = the angle of elevation.

tanθ =77/2020

tanθ = 0.038 12

      θ = tan⁻¹0.038 12

      θ = 2.2°