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.
Let Hiking students = H
Let Swimming students = S
Let Archery students = A
We are given
H : S : A = 5 : 6 : 11
Let
H= 5x
S = 6x
A = 11x
We have to find (A&S)/A
Statement 1All students enrolled in Hiking are also enrolled in Archery.
This means H is included in A
=> 5x of H is part of 11x
Total = 5x + 6x + 11x - {Part of two groups} + {Part of three groups}
=> Total = 5x + 6x + 11x - {A&H} - {A&S} - {S&H} + {A&H&S}
=> Total = 5x + 6x + 11x - 5x - {A&S} - {S&H} + {A&H&S}
=> Total = 6x + 11x - {A&S} - {S&H} + {A&H&S}
=> Total = 17x - {A&S} - {S&H} + {A&H&S}
With this there isn't enough information to figure out the value of (A∩S)/A
Not SufficientStatement 2Every student enrolled in Archery is also enrolled in at least one other group
H and S are also enrolled in A as 5x + 6x = 11x
=> Everyone is enrolled in Archery
=> Total = 11x
Total = 5x + 6x + 11x - {Part of two groups} + {Part of three groups}
=> 11x = 5x + 6x + 11x - {A&H} - {A&S} - {S&H} + {A&H&S}
=> 11x = 5x + 6x + 11x - {A&H} - {A&S} - 0 + {A&H&S}
=> 11x = 5x + 6x + 11x - 5x - 6x - 0 + {A&H&S}
=> 11x = 11x + {A&H&S}
=> {A&H&S} = 0
Hence, none of the students were part of all three groups
=> {A&S} = 6x
Now (A∩S)/A = {A&S}/A
=> (A∩S)/A = 6x/11x = 6/11
SufficientIMHO Option B