If (a + b) : (b + c) : (c + a) = 7 : 8 : 5 and a + b + c = 20 then the value of c is :
Answer & explanation
Correct answer: option 2
(a + b) : (b + c) : (c + a) = 7 : 8 : 5
2(a + b + c) = 20x
a + b + c = 10x = 20
x = \(\frac{20}{10}\) = 2
Now,
⇒ (a + b + c) - (a + b) = 20 - 7x = 20 - 14 = 6
⇒ c = 6