dear, also for question 127, i think the answer should be C.
join 2 event = x, did not join 2 event =x
join only one event = 2x. total is 200=x+x+2x. hence x=50 which is the number of people who did not join 2 event
hello, another note, i just realized that for question 176, if x>0 and y<0, it seems that A is the correct answer.
because \x+y\=3 (x>0, y<0), --> then \x-y\ for sure not is equal to 3. am i correct?
hello, thanks for your reply. but I still think answer should be A
for II, if x=3, y=-6, then \\x\-\y\\=3 and \x+y\=3, all the other values for x and y, we can get \x+y\=other value. hence only I is sufficient let me know if you have any questions. thanks.