Question

The table lists the drinking habits of a group of college students. If a student is chosen at random, find the probability of getting someone who is a woman or a heavy drinker. Round your answer to three decimal places.

Sex: Non-drinker Regular Drinker Heavy Drinker Total   

Man 135 52 5 192

Woman 187 21 15 223

Total 322 73 20 415

Answer 1

Total Sample = 415

Total women in the sample = 223

Total Heavy Drinker in the sample = 20

Total woman and heavy drinker in the sample = 15

P(woman) = Total women in the sample / Total Sample = 223 / 415 = 0.5373494

P(heavy drinker) =  Total Heavy Drinker in the sample / Total Sample = 20 / 415 = 0.04819277

P(woman and heavy drinker ) = Total woman and heavy drinker in the sample / Total Sample = 15 / 415 = 0.03614458

Probability of getting someone who is a woman or a heavy drinker = P(woman or heavy drinker )

= P(woman) + P(heavy drinker) - P(woman and heavy drinker )

= 0.5373494 + 0.04819277 - 0.03614458

= 0.549