Option B is the correct answer.
Lets understand the question and information mentioned in it before trying to solve it.
So the question starts by telling us that at a charity event everyone who is expected attending the event belongs to exactly one of the six groups:
donors, press, volunteers, entertainers, organizers, or sponsors. Then it tells us about the information about the number of expected people per group who will be the part of the event i.e. "Among the invited guests, 4/7 were donors, 1/5 were press, and the remainder were divided equally among the other four groups". Then the question gives us information about the number of people who actually attended the event i.e. "On the day of the event, however, twice as many press guests arrived as were invited, only half of the invited volunteers attended, and the entertainers did not attend due to a last-minute boycott. The donors, organizers, and sponsors showed up as expected". And in the end asks us what fraction of people who actually attended the event were donors.Now lets try solving the question but before that lets assume the total expected number of people from all the six groups to be 70 people, we have take total expected number to be 70 so that we can get the values in integer form which will make the calculations easy for us as well as the number of people can never be in decimal for so that's the another reason.
So, as per our assumption Total expected count of people = 70 People
Total expected count of Donor = 70*(4/7) => 40 People
Total expected count of Press = 70*(1/5) => 14 People
Total expected count of V
olunteers = (70-40-14)*(1/4) => 16*(1/4) => 4 PeopleTotal expected count of E
ntertainers = 16*(1/4) => 4 People Total expected count of O
rganizers = 16*(1/4) => 4 People Total expected count of S
ponsors = 16*(1/4) => 4 People Now as per the question the information regarding the number of people who actually attended the event is "
twice as many press guests arrived as were invited, only half of the invited volunteers attended, and the entertainers did not attend due to a last-minute boycott. The donors, organizers, and sponsors showed up as expected".Members of Press who actually attended the event = 2*14 => 28 People
Members of V
olunteers who actually attended the event = 4/2 => 2 People
Members of E
ntertainers who actually attended the event = 0 People
Members of Donors who actually attended the event = 40 People
Members of Organizers who actually attended the event = 4 People
Members of Sponsors who actually attended the event = 4 People
Total number of people who actually attended the event = 28+2+0+40+4+4 => 78 People.
Now the asks us what fraction of people who actually attended the event were donors = Number of donors who attended the event/Total number of people who attended the event
= 40/78 =>
20/39 (Option B)So from here we get Option B as our answer.Bunuel
At a charity gala, each invited guest belonged to exactly one of six groups: donors, press, volunteers, entertainers, organizers, or sponsors. Among the invited guests, 4/7 were donors, 1/5 were press, and the remainder were divided equally among the other four groups. On the day of the event, however, twice as many press guests arrived as were invited, only half of the invited volunteers attended, and the entertainers did not attend due to a last-minute boycott. The donors, organizers, and sponsors showed up as expected. What fraction of the actual attendees were donors?
A. 4/7
B. 20/39
C. 4/9
D. 2/5
E. 10/39