Bipartite Graphs and Matchings · Medium problem

A company's reporting structure is a complete binary tree of depth $3$: one top executive, who has $2$ direct reports, each of whom has $2$ direct reports of their own, each of whom has $2$ direct reports of their own (a total of $1+2+4+8=15$ people). Since every tree is bipartite, split the company into two committees so that every direct-report link joins someone in one committee to someone in the other. What is the size of the LARGER committee?