(N/A) Steps of construction:
$1$. Draw an equilateral triangle $\Delta XYZ$ with each side equal to $6\, cm$.
$2$. Draw a ray $XS$ making an acute angle with $XY$ at vertex $X$ on the side opposite to $Z$.
$3$. Locate $5$ points $X_1, X_2, X_3, X_4, X_5$ on ray $XS$ such that $XX_1 = X_1X_2 = X_2X_3 = X_3X_4 = X_4X_5$.
$4$. Join $X_4$ to $Y$. Draw a line through $X_5$ parallel to $X_4Y$ intersecting the extended line segment $XY$ at point $M$.
$5$. Draw a line through $M$ parallel to $YZ$ intersecting the extended line segment $XZ$ at point $N$.
$6$. Thus,$\Delta XMN$ is the required triangle similar to $\Delta XYZ$ with scale factor $\frac{5}{4}$.