If you could, post the memoir title so someone can read it and assist you with the question...
The mode stands for the number in a series found the most.
In this series you have:
three 4s
two 17s
one 27
one 29
one 20
one 24
and one 34
The mode, or number most found, is 4.
What are the options?
A good question would be : What was the main idea?
