Q1 Suppose that in a senior college class of 500 students it

Q1: Suppose that in a senior college class of? 500 students it is found that 210 smoke, 258 drink a lot of soft drinks, 216 cat between meals, 122 smoke and drink soft drinks, 83 eat between meals and drink soft drinks, 97 smoke and cat between meals, and 52 engage in all these three of these bad health practices. If a member of this senior class ?s selected at random, find the probability that the student (a) Smokes but does not drink soft drinks. (b) Eats between meals and drinks soil drinks but does not smoke. (c) Neither smokes nor eats between meals.

Solution

a) Number of students that smokes but does not drink soft drinks = number of students that smokes - number of students that smoke & drinks soft drink = 210 - 122 = 88

Therefore, P( smokes but does not drink soft drinks) = 88/500 = 0.176

b) Number of students that eats between meals and drinks soft drinks but does not smoke = Number of students that eats between meals and drinks soft drinks - number of students engaged in all three practices = 83 - 52 = 31

Therefore, P(eats between meals and drinks soft drinks but does not smoke) = 31/500 = 0.062

c) Number of students that either smokes or eats between meals = number of students that smokes + number of students that eat between meals - number of students that smokes and eat between meals = 210 + 216 -97 = 329

Thus, Number of students that neither smokes nor eats between meals = 500 - Number of students that either smokes or eats between meals = 500 - 329 = 171

Therefore, P(neither smokes nor eats between meals) = 171/500 = 0.342