My attempt: $$m_1=2s_1=s_2$$ $$m_2+s_2=180$$
Let $x$ be the age of the son and $y$ the father. We have first off $2x=y$ right now. The second sentence says that "when the son is the age of the father...", we note that right now the son is $x$ and his father is $y=2x$, so when the son is the father's age, that is when the son is $2x$ years old, their ages add to 180. The number of years that pass from the time that the son is $x$ till the time the son is $2x$ is simply $x$. Thus $(2x) + (y+x) = 180$. Now we have a system $$2x=y \\ (2x) + (y+x) = 180$$ The solution is $x=36$ and $y=72$. Those are the ages of the two right now, while the ages later on are $72$ and $108$ respectively.