Sangwook on January 1, 2015
I got right answer for this question though, I can't help but wonder about the right way of conversing the first sentence of the stimulus into sufficient and necessary condition in order to solve out this type of strengthen question.
When I tried to figure this out, I conversed 1st sentence like the following:
"Having an efficient, attractive subway system makes good economic sense" ===> " If (we) have an efficient, attractive...., it makes (us) have good economic sense"
But, I couldn't find answer with such S&N condition. So, I tried to reverse both conditions as like the following:
====> "(To) make good economic sense, (we must) have an efficient, attractive subway system."
Then, I could smoothly fugue this out.
In this light, I'm still confused why my first attempt is wrong. Is it possible to make two different S&N condition from the sentence like that?? If it isn't,please explain why which one is right and which one is wrong.
Melody on January 5, 2015
Sangwook on January 6, 2015