Answer:
Step-by-step explanation:
First add all of the numbers together
25+22+13+14+21=82
Now add a variable like X since we don't know the age of the sixth, and divide it by 6 since there are 6 people in the class.
82+X/6=22
(22 is the mean age)
Now solve for the equation
82+X=132
so X =50