# If Malpighi's delivery is first and Leacock's delivery is third, then which one of the following must be true?

jack515 on December 16, 2018

question 20

I wanted clarification on how H is not before L here, making it M,H,L. I thought rule 3 made it so If F>M -> L>H. F is not earlier than M so isnt H before L?

Replies

jack515 on December 16, 2018

nvm lol

Ravi on December 17, 2018

@jack515,

it sounds like you might have figured it out, but here's further clarification in case you need it. H could be before L in this question, but it doesn't have to be. You could also have F before L.

Rule 3 does state if F - M, then L - H. However, what I think may have been tripping you up is properly understanding the contrapositive of this rule. The contrapositive of this rule is if H - L, then M - F. If the sufficient condition of F - M, then L - H is failed, it does not mean that the necessary condition must also fail. What it means is that the rule then becomes irrelevant.

This is why F can also be in the second position, which is why the correct answer is (E) because it's the only answer that must be true...Kanzaki's delivery has to be sixth (last).