PT12.S1.Q14 - Morris High School has introduced

Seriousbird

If someone could help me out on this one I am completely lost.

I know you can eliminate A and B and they both talk about what proportion of part time/full time employees quit before the policy was introduced and we only have information about what happened after the new policy was introduced.

I guess I need help in understanding answer choices C-E. I thought C was the correct answer because if more new full time employees are hired, then the conclusion does not follow from the premises. If more new full time employees are hired then it could be the same amount quitting in their first year even with the percentage 1/3 full time.

I'm not a mathematician, so I could be totally off. If someone could help me I would be most appreciative.

Sami

Hey,

So our premise says: fact 1: 1/4 of Part time now quit. fact 2: 1/3 of Full time teachers quit.
Conclusion: more Full time teachers than part time teacher quit.

So I think you are correct in following that something is going on with how many teachers are being hired. The only information we know is percent of Part time relative to total number of part time quitting. The same goes for full time teachers. We cannot conclude from percentage which group has more numbers of teacher quitting. We would need to know the total number of Part time and full time to conclude which group has more teachers quitting.

So, the questions is asking what is the argument failing to rule out: like if something was true, what could possibly make this conclusion not work out.

So you are right in ruling out A and B. We don't care who quit more before the policy was instituted.

Answer choice "C" is saying More New Full time teacher were hired than part time. So if 100 new Full time teachers were hired, then about 33 of them quit. And lets say only 10 new Part time teachers were hired, then only about 2 or 3 quit. This is in line with our conclusion. More Full time teachers 33 versus Part time teachers quit.

But if like answer choice "D" says, more Part time teachers were hired, 100 vs only 10 full time teachers. Then more Part time teachers quit despite having a lower percentage of teachers quitting for part time.

Answer choice "E" says that there are same # of Part time and full time teachers are employed. Lets say now both are hundred. This would lead to the conclusion that about 25 PT teachers quit and more about 33 Full time teachers quit. This also agrees with our conclusion more full time than part time teachers quit.

* I think the examples are great in going over a question but a quick way to come to the answer might be that the guy in the argument is assuming that higher percentage of quitting actually means a higher number of quitting. We know they, higher percent does not mean higher number, and hence are not the same thing. So to find a flaw just flip it and say what if the higher percentage group had a lower number of people, and lower percentage had a higher number of people. Then our conclusion would not follow.

catherine-1

@Sami Great explanation! Thanks