A 5-ary tree in which every internal node has exactly 5 children. The number of left nodes in such a tree with 8 internal nodes will be:
In a complete n-ary tree, $L = (n-1) * I + 1$ where L = No. of leaves, I = No. of Internel nodes
Here n = 5, I = 8
Therefore, L = (5-1) * 8 + 1 = 4 * 8 + 1 = 33
The question was maybe wrongly printed.
Since Official Answer key is 9 (i.e. ALL Correct)
Not sure though!