Question

If x:y::3:5, find the ratio 4x+9y:8x+9y.

• A. 23:19
• B. 19:23
• C. 3:5
• D. 5:3

Answer 1

The correct option is B

19:23

Given that $\frac{x}{y}=\frac{3}{5}$

Now, $\frac{4x+9y}{8x+9y}=\frac{y(\frac{4x}{y}+9)}{y(\frac{8x}{y}+9)}$

$=\frac{\frac{4x}{y}+9}{\frac{8x}{y}+9}$

$=\frac{4\times \left(\frac{3}{5}\right)+9}{8\times \left(\frac{3}{5}\right)+9}$

$=\frac{57}{69}$

$=\frac{19}{23}$