Question 29
In some country there are three cities $A$, $B$ and $C$. Between each of the two cities there are several roads (at least one) and all the roads are two-way. Apart from the direct road links between two cities, there are also indirect road links. An indirect road link between $X$ and $Y$ consists of a road that connects $X$ with a third city $Z$ and a road that connects $Z$ and $Y$.
It is known that there are altogether 43 road links between $A$ and $B$, and altogether 29 road links between $B$ and $C$. How many road links can there be between $A$ and $C$ altogether? (Sweden 2012)
It is known that there are altogether 43 road links between $A$ and $B$, and altogether 29 road links between $B$ and $C$. How many road links can there be between $A$ and $C$ altogether? (Sweden 2012)