Answer:
the percent of increase is 24%
Step-by-step explanation:
The percent of increase in general could be calculate as:
where Vf is final value and Vi is initial value.
From the question we know that Vi is equal to 25 and Vf is equal to 31. Replacing this values on the equation we get:
That's mean that at second attempt the percent of increase is 24%, taking into account that at the first attempt a student get 25 questions correct.