In a local cellular phone area, company A accounts for 60% of the cellular phone market, while company B accounts for the remaining 40% of the market. Of the cellular calls made with company A, 1% of the calls will have some sort of interference, while 2% of the cellular calls with company B will have interference. If a cellular call is selected at random, what is the probability that it will not have interference?
A) 0.14
B) 0.014
C) 0.028
D) 0.986

Question

Quizplus · Accepted Answer

To find the probability that a call will not have interference, we need to find the complement of the probabilities of interference for both companies and then calculate the overall probability.

For company A,
Probability of interference = 1%
Probability of no interference = 99%

For company B,
Probability of interference = 2%
Probability of no interference = 98%

Overall probability of selecting a call with no interference can be calculated using the weighted average of the probabilities of no interference for both companies:

(0.6 x 0.99) + (0.4 x 0.98) = 0.594 + 0.392 = 0.986

Therefore, the probability that a selected cellular call will not have interference is 0.986.

In a Local Cellular Phone Area, Company a Accounts for 60