Digital PSAT Math Practice Question 272: Answer and Explanation

Question: 272

If is equivalent to which of the following?

• A.
• B. 6
• C. -3
• D.

Correct Answer: B

Explanation:

(B) Notice that the expression the question is asking about is just the reciprocal of the left side of the first expression. Therefore, it will equal the reciprocal of the right side of the first expression. Because the reciprocal of is 6, the answer is choice (B).

Alternatively, if you do not recognize that it is the reciprocal, you can solve for x in the first equation and then plug this into the second expression:

If , then multiplying both sides by gives . Plugging this into your expression gives