The ratio of to is . If is added to and is subtracted from , the new ratio of to is . What is the value of ?

Answer and explanation

Correct answer: C.

  1. Step 1: Let and . Formulate the ratio equation: .
  2. Step 2: Cross-multiply and solve for : .
  3. Step 3: Compute and : and . Sum them: .
Answer
.
Why not the others: is the value of alone; adds rather than subtracts the constant term in the final step in solving for ; is the value of alone; is .

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