The average of 12, 21 and $x$ is 18. What is the value of $x$?
Question:
The average of 12, 21 and $x$ is 18. What is the value of $x$?
Answer:
Let's think step by step.

user
21
The average of 12, 21 and $x$ is 18. What is the value of $x$?
train