Exercise · ZW-TREE-005 · ★★☆ Intermediate
A tree with 7 vertices has one vertex of degree 4, one of degree 3, and the rest are leaves (degree 1). How many leaves does it have?
Choose one option.
Show answer
- B. 5
Explanation
That leaves \(7-2=5\) vertices, all of degree 1. Check: \(4+3+5=12=2\cdot 6\), as required for a tree with 6 edges.
Review the concept: Tree
A tree \(T=(V,E)\) is a connected graph that contains no cycles.
\[|E|=|V|-1\]
More practice problems: tree
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- ZW-TREE-006 One edge is removed from a tree. How many connected components does the resulting graph have?
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