<p>18) If Marta is assigned to Project A, then the project will be completed on time. Which of the following can be concluded?</p>
<p>A. If project A is completed on time, then marta must have been assigned to project A.</p>
<p>B. If marta was assigned to project b, then project a will not be completed on time.</p>
<p>C. If project A is not completed late, then no one other than marta was assigned to project A.</p>
<p>D. If marta is not assigned to project A, then project A, then Project A will be completed late.</p>
<p>E. If the project is completed one week late, then marta was not assigned to Project A.</p>
<p>The answer I chose was D but it was wrong and the correct answer is E. Can someone clarify and possibly give me more tips on these kind of logic problems? Keep in mind that this is from a PR book.</p>
<p>E is correct because the problem states that If Marta is assigned to project A it will be completed on time. Because it was not completed on time, we can conclude that Marta did not do project A because if she had, it would have been completed on time.</p>
<p>Also, D is not correct because we don’t know that Martha is the only one who could complete Project A on time. Someone else could be assigned to the project and complete it on time.</p>
<p>One of the most basic theorems in logic is that the contrapositive of a true statement is true.</p>
<p>Statement: If <a> then <b>.</b></a></p><a><b>
</b></a><b><p><a>The contrapositive of the above statement is: If not <b> then not </b></a><b><a></a></b></p><b><a>
<p>If the statement is true, then the contrapositive of the statement is true.</p>
<p>In this particular case the statement is:
If Marta is assigned to Project A, then the project will be completed on time.</p>
<p>The contrapositive is:
If the project is not completed on time, then Martha was not assigned to it.</p>
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