Bunuel
At a summer camp, there are exactly three activity groups: Hiking, Swimming, and Archery, and every student is enrolled in at least one of these groups. For every 5 students in Hiking, there are 6 in Swimming and 11 in Archery. Among those enrolled in Archery, what fraction are also enrolled in Swimming?
(1) All students enrolled in Hiking are also enrolled in Archery.
(2) Every student enrolled in Archery is also enrolled in at least one other group.
The ratio of the three activity is given to us
Hiking : Swimming : Archery = 5 : 6 : 11
(1) All students enrolled in Hiking are also enrolled in Archery.
Let's assume there are just 5 students in hiking, 6 students in swimming and 11 students in archery.
Among these 11 students who are enrolled in archery 4 students are enrolled in swimming as well.
Ratio = 4/11
Another possibility could be among these 11 students who are enrolled in archery 2 students are enrolled in swimming as well.
Ratio = 2/11
We can have multiple possible combinations.
Statement 1 is not sufficient.
(2) Every student enrolled in Archery is also enrolled in at least one other group.
Let's assume there are just 5 students in hiking, 6 students in swimming and 11 students in archery.
We have to divide these 11 students in a manner that they are assigned to either Hiking or Swimming. As the max capacity of Hiking is 5, the remaining must be in swmming. Hence there is no possible way other than to put 5 in hiking and 6 in swimming.
Ratio is always 6 /11
The statement alone is sufficient.
Option B