A business school club, Friends of Foam, is throwing a party at a local bar. Of the business school students at the bar, 40% are first year students and 60% are second year students. Of the first year students, 45% are drinking beer, 40% are drinking mixed drinks, and 15% are drinking both. Of the second year students, 30% are drinking beer, 30% are drinking mixed drinks, and 20% are drinking both. A business school student is chosen at random. If the student is drinking beer, what is the probability that he or she is also drinking mixed drinks?
Choose the correct choice from the following choices:
A) 1/2 B) 4/7 C) 10/17 D) 7/24 E) 7/10
Suppose there are 100 students   Group 1/2 : 40% = 40 students   45% drink beer = 18   40% mixed = 16   15% both = 6   Group B 60% = 60   30% beer= 18   30% mixed = 18   20% both= 12   now we need both ( beer + mixed = both)   probability = total beer drinker = 18+18= 
<gadget id="calculator">18+18</gadget>
<output>36</output>
36 and both= 20   thus 18/36 = 1/2   Hence 1/2
<result>A</result>
A business school club, Friends of Foam, is throwing a party at a local bar. Of the business school students at the bar, 40% are first year students and 60% are second year students. Of the first year students, 45% are drinking beer, 40% are drinking mixed drinks, and 15% are drinking both. Of the second year students, 30% are drinking beer, 30% are drinking mixed drinks, and 20% are drinking both. A business school student is chosen at random. If the student is drinking beer, what is the probability that he or she is also drinking mixed drinks?