You have a grade of 85 & 90
What grade must you make on the next test to pass the class with a 90 grade average?

You need to get a 95 on the next test to have a 90 grade average.

Step-by-step explanation:

(85 + 90 + n)/3 = 90

Step 1:  Multiply both sides by 3

(85 + 90 + n)/3 * 3 = 90 * 3

85 + 90 + n = 270

Step 2:  Subtract 85 from both sides

85 + 90 + n - 85 = 270 - 85

90 + n - 90 = 185 - 90

n = 95

 You need to get a 95 on the next test to have a 90 grade average.

95

Step-by-step explanation:

Average: 90

(85+90+X)/3 = 90

(175 + X) = 90×3

175 + X = 270

X = 95