LIC AAO Model Paper 3

According to the question
$\frac{2}{5}$ A + 40 = $\frac{2}{7}$ B + 20
= $\frac{9}{17}$ C + 10 = x (let)
⇒ A = $\frac{5}{2}$ (x - 40)
B = $\frac{7}{2}$ (x - 20) and C = $\frac{17}{9}$ (x - 10)
∴ $\frac{5}{2}$ (x - 40) + $\frac{7}{2}$ (x - 20)
+ $\frac{17}{9}$ (x - 10) = 600
⇒ $\frac{45\left(\mathit{x}-40\right)+63\left(\mathit{x}-20\right)+34\left(\mathit{x}-10\right)}{18}$ = 600
⇒ $\frac{45\mathit{x}-1800+63\mathit{x}-1260+34\mathit{x}-340}{18}$ = 600
⇒ 142x- 3400 = 18x600
⇒ 142x = 10800 + 3400 =14200
⇒ x = $\frac{14200}{142}$ × 100
∴ A's share = $\frac{5}{2}$ (100 40)
= Rs. $\left(\frac{5}{2}\times 60\right)$ = Rs. 150