Question

Let T be a tree with 10 vertices. The sum of the degrees of all the vertices in T is

• A. 18

Answer 1

The correct option is A 18
Here in this tree, n = 10
$\sum \text{degree}=2|E|$
where |E| represents number of edges.

In a tree, |E| = n - 1
= 10 - 1 = 9

So $\sum \text{degree}=2\times 9=18$