He answered 92% of the questions correctly.
To find the percent of questions he answered correctly you need to subtract 90 by 7 so that you get the questions that were correct which will give you 90-7 and you’ll get 83.
Next you want to find what 83 is of 90 so you would use division. 83/90≈0.9223. Next you want to round by the nearest hundredth to get the percent. The rounding will then become 0.92. 0.92 can be changed into 92%.