Question

A company that manufactures smartphones makes 70% of the phones with a touch screen and 55% of the phones with HD movie capability. 30% of the phones have both a touch screen and HD movie capability. What is the probability that a smartphone chosen at random has either a touch screen or HD movie capability?

Answer 1

Given:

probability of touch screen P(a) = 70% = 70/100 = 0.7

probability of HD movie capability P(b) = 55% = 55/100 = 0.55

probability of HD movie capability and touch screen P(ab) = 30% = 30/100 = 0.3

To Find:

probability of either HD movie capability or touch screen P(x) =?

Step-by-step explanation:

Now, from the inclusion-exclusion rule, we know that

P(x) = P(a) + P(b) - P(ab)

on putting the values in above equation

P(x) = 0.7 + 0.55 - 0.3 = 0.95

Thus, the probability of either HD movie capability or touch screen is 0.95 or 95%