Answer:
Votes received by Billy =15
Step-by-step explanation:
Given:
Total students in the class = 20
Billy receives 3 times more vote than Keeton.
To find the number of votes Billy receives.
Solution:
Let number of votes Keeton gets 
∴ Billy received
votes
Expression for total votes can be given by ⇒ 
Total votes =20 as number of students is 20.
So, the equation to find
is:

Solving for 
⇒ 
Dividing both sides by 4.

∴ 
∴ Votes received by Keeton = 5
Votes received by Billy =
= 15