The average of 6 test scores is calculated by dividing the sum of the six scores by six. Let the unknown score be x.
(x + 90 + 98 + 96 + 94 + 85)/6 = 92
Add the numbers on the left side.
(x + 463)/6 = 92
Multiply both sides by 6.
(x + 463)/6 * 6 = 92 * 6
x + 463 = 552
Subtract 463 from both sides.
x = 89
Answer: 89