Bunuel
In Garfield School, 250 students participate in debate or student government or both. If 40 of these students participate in both debate and student government, how many of these students do not participate in debate?
Given: {250}={Debate}+{Government}-{40}, (notice that 250 students participate in debate or government or both, so no need of the group {neither} here).
Question: how many of these students do not participate in debate? Which means how many participate in government ONLY: {Government}-{40}=? So basically we need to find the value of {Government}.
(1) 80 of the students do not participate in student government --> {Debate}-{40}=80. We know {Debate}, we can get {Government}. Sufficient.
(2) In Garfield School, 150 students do not participate in either debate or student government. Useless info. Not sufficient.
Answer: A.
Thanks for the explanation bunnel. I think second option is contradicting question stem where you have pointed out "(notice that 250 students participate in
debate or
government or
both, so no need of the group {neither} here)"
but neither is given in the second option.
Yes, I see your point but it's not so: there is no need for {neither} in the formula {250}={Debate}+{Government}-{40}, means that
there are no student who do not participate in either debate or government, but it doesn't mean that such students doesn't exist at all. Statement (2) says that there is such a group of 150 people apart of the group of 250.
Hope it's clear.