You can put this solution on YOUR website! If you are asking .. How many questions out of 120 do I need to correctly answer to get 85% correct?
Then:
85% of 120 = x the variable x represents the number needed
.85 x 120 = x changed percentage to a decimal and multiplied (note the
word of indicates multiplication)
102 = x ..therefore you would need to correctly answer 102 questions.