Mathematics > Standard Multiple Choice

Read the following SAT test question and then click on a button to select your answer.

If a, b, and c are numbers such that a/b=3 and b/c=7, then (a+b)/(b+c) is equal to which of the following?

(A) 7/2
(B) 7/8
(C) 3/7
(D) 1/7
(E)  21

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The Correct answer is A.

Explanation

From  is implied that  (1)

And from  is implied that  (2)

If we multiply (1) and (2) together, we have that  (  is canceled out).