Answer:
14.29% probability that Marlon's friend will think of the number 9
Step-by-step explanation:
A probability is the number of desired outcomes divided by the number of total outcomes.
In this problem, we have that:
There are 7 numbers from 5 to 11(5,6,7,8,9,10,11)
9 is one of them
So
![p = \frac{1}{7} = 0.1429](https://tex.z-dn.net/?f=p%20%3D%20%5Cfrac%7B1%7D%7B7%7D%20%3D%200.1429)
14.29% probability that Marlon's friend will think of the number 9