Jose's math grade is the mean of his three exams. His grades of the first two exams were 82 and 93. What grade must he earn on his third exam to have of at least 90 for the class?

Respuesta :

So we let the mark of his third exam be x
(82+93+x)/3=90
Multiply both sides by 3
82+93+x=270
x=93
98
because ..
82+93+98=273
273/3=91