The number in parentheses BEFORE the slash sign is called the Computed Distance (CD) this shows the total metric of the destination network over the particular neighbor. The CD is computed as the RD of the neighbor plus the cost of the link between that router and the neighbor.
For each destination network there is exactly one CD and one RD per each neighbor. These are displayed in the via lines of the ‘show ip eigrp topology‘ output.
The path with the lowest CD is installed into the IPv4 RIB.