Since $50 = 4 \cdot 12 + 2$, according to the pigeonhole principle we will have at least 13 points colored in the same color. Using these 13 points we construct $\binom{13}{3} = 286$ different triangles, since there are no three collinear points.

We will prove that there are at most $12 \cdot 13 = 156$ isosceles triangles. In fact, there are $\binom{13}{2} = 78$ different line segments. Each of them can be the basis at most two different isosceles triangles (because there are not three collinear points). Therefore there are at most $\binom{13}{2} \cdot 2 = 78 \cdot 2 = 156$ isosceles triangles. Thus we can construct at least $286 - 156 = 130$ scalene triangles.