Colin predicted whether he got answers right or wrong in his 50 question exam. He identified the 12 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 42 out of 50 in the test.
What is the percentage accuracy he had with predicting his scores

92.86%

Step-by-step explanation:

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 :

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

probability for j is 1/4

while

a is 1/6