Colin predicted whether he got answers right or wrong in his 50 question exam. He identified the 8 questions he thought he got wrong. It turns out that Colin got 5 questions right that he thought he got wrong. Colin also got a total score of 45 out of 50 in the test. What is the percentage accuracy he had with predicting his scores?

Respuesta :

Total questions, T = 50.

Colin thought 8 questions were right.

Colin got 5 questions right that he thought he got wrong.

Total score, s = 45.

So, actual number of questions which are wrong are 5.

Score according to him = 50 - 8 = 42.

Now, we know percentage accuracy is given by :

[tex]\% =100- \dfrac{|Actual\ value-Theoretical\ value|}{Actual\ Vlaue}\times 100\\\\\%=100-\dfrac{|45-42|}{42}\times 100\\\\\%=100-7.14 \%\\\\\%=92.86\%[/tex]

Therefore, percentage accuracy he had with predicting his scores is 92.86%.

Hence, this is the required solution.