New York City SHSAT 2017

(Marvins-Underground-K-12) #1

If/then questions test your understanding of cause-and-effect scenarios. You are given a statement that tells you, “If X happens, then
Y occurs.” There is only one deduction that you can make from an if/then statement—the contrapositive.


You may never have heard of a contrapositive before. This doesn’t matter. All you have to know about the contrapositive is that it is
formed by reversing and negating the if/then statement. Here’s how it works. Say you have the following statement:


This makes a certain amount of sense, doesn’t it? If I live in New York, then I have to be a New Yorker.


IF/THEN TIP


Make sure the statement is in if/then order.

To find the contrapositive, you reverse the if and then clauses and make both negative. It should look like this.


This follows from the first statement. If living in New York makes me a New Yorker, then if I am not a New Yorker, I cannot live in
New York.


Try a couple of these on your own.


If I live in New York, then I am a New Yorker.

If I am not a New Yorker, then I do not live in New York.
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