2024 · Q46
If (a + b) : (b + c) : (c + a) = 5 : 7 : 6, then what is the value of (a - b + c) : (a + b - c)?
Elementary MathematicsRatio and Proportion
- A1 : 1
- B2 : 3
- C3 : 1
- D4 : 3
Explanation
From (a+b) : (b+c) : (c+a) = 5 : 7 : 6, adding the three gives a + b + c = 9k. Hence a = 2k, b = 3k, c = 4k. Then (a − b + c) : (a + b − c) = 3k : k = 3 : 1, option (c).