Answer
$3$
Work Step by Step
$\left[\begin{array}{lll}
\text{What number} & \rightarrow & x...\\\\
\text{multiplied by the numerator} & & \\
\text{and added to the denominator of 4/5} & \rightarrow & \dfrac{4x}{x+5} \\ \\
\text{... equivalent to 3/2} & \rightarrow & =3/2
\end{array}\right]$
$\displaystyle \frac{4x}{x+5}=\frac{3}{2}\qquad/...\times 2(x+5)$
$4x(2)=3(x+5)$
$8x=3x+15\qquad/...-3x$
$5x=15\qquad/...\div 5$
$x=3$
