On a test, 81.3% of the student got a certain

As the % increases this means, the new student got it correct
Let original number of students who originally attempted be x
The number of students who got the correct answer = 0.813x
After the new student:
Number of students who got it correct = 0.813x + 1
Total number of students = x + 1
% correct = \frac{0.813x + 1}{x + 1} * 100 = 82.4
81.3x + 100 = 82.4x + 82.4
1.1x = 17.6
x = 16
x + 1 =17
Ans. 17

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Thank you so much.

On a test, 81.3 %81.3% of students got a certain question correct on their first try. After another student attempted the question, the success rate was 82.4 %82.4%. If no additional students attempted the question, how many people attempted the question in total?

This is what my logic is - but please do verify if it is the correct answer!

I am getting 90.90. I don’t know the correct answer. Can you guys help?

They are asking for the total number of students who attempted the question.

An additional step I can provide you that’s not already in this thread is:

x = number of students who answered correctly
t = total number
x/t = 81.3% or 81.3/100

x + 1 = one more student got it correct
t + 1 = one more student attempted it so the total must be added as well
x+1/t+1 = 82.4% or 82.4/100

Notice that we have 2 equations with 2 variables so we can solve for t.