So, we have the percentage she gets which is, 90% and the number of questions she answers correctly, which is 27
To find the number of questions in the exam, make an equation
(90% = [tex] \frac{90}{100} [/tex] = 0.9)
[tex] \frac{90}{100} [/tex] = [tex] \frac{27}{x} [/tex]
cross multiply and equate them
90x = 27 x 100
90x = 2700
divide by 90 on either sides to isolate x in order to find the answer
[tex] \frac{90x}{90} = \frac{2700}{90} [/tex]
90 and 90 cancels out
x = 30
So your final answer will be, there were 30 questions in the exam paper.
