Question

What number should be added to the terms of 3:7 to make the ratio 2:3?

• A. 3
• B. 4
• C. 5
• D. 6

Hint:

When solving problems with ratios, use cross-multiplication to set up an equation to find the unknown.

Answer 1

The Correct Option is C

Let the number to be added to both terms be \( x \). The new ratio becomes: \[ \frac{3 + x}{7 + x} = \frac{2}{3} \] Now, cross-multiply to solve for \( x \): \[ 3(3 + x) = 2(7 + x) \] \[ 9 + 3x = 14 + 2x \] \[ 3x - 2x = 14 - 9 \] \[ x = 5 \] Thus, the number to be added is 5. Therefore, the correct answer is (C) 5.