Question

Exercise

Answer 1

X - nominator
y - denominator

$\frac{3x}{y+12}=\frac{3}{4}\\ \frac{x+7}{3y}=\frac{1}{2}\\\\ 3(y+12)=12x\\ 2(x+7)=3y\\\\ 3y+36=12x\\ 2x+14=3y\\\\ 2x+14+36=12x\\ 10x=50\\ x=5\\\\ 3y=2\cdot5+14\\ 3y=10+14\\ 3y=24\\ y=8\\\\ \frac{x}{y}=\boxed{\frac{5}{8}}$