The student answered 92.5% of the test correctly.
Essentially, the student who scored three questions on a 40-question test incorrectly, the fraction would be 37/40 since they only missed three questions out of 40, so you subtract three from the 40, which gets you 37.
Now that you have the fraction form, you can change the fraction into a decimal.
[tex] \frac{37}{40} = 0.925[/tex]
If you turn 0.925 into a percentage, you will get 92.5%, which is the score the student got on the test.