Respuesta :

(80+82+x)/ 3>=74
(80+82+x)=3x74
162+x>=222
x>=60
she has to have 60 or above.
altavistard
Find this:

 87 + 83 + x
----------------- = 74
           3

Mult. both sides by 4:  87+83+x = 222, and  170 + x = 222

Then x = 222-170 = 52.

With a score of 52 or better on her 3rd test, J. would have an average of 74 or better.