In answering a question on a multiple choice test, a student either knows the answer or guesses. Let `3/5` be the probability that he knows the answer and `2/5` be the probability that he guesses. Assuming that a student who guesses at the answer will be correct with probability `1/3` , what is the probability that the student knows the answer given that he answered it correctly

Explanation

To solve the problem, we will use Bayes' theorem. Let's break it down step by step.

### Step 1: Define the Events
- Let \( E_1 \) be the event that the student knows the answer.
- Let \( E_2 \) be the event that the student guesses the answer.
- Let \( A \) be the event that the student answers correctly.

### Step 2: Write Down the Given Probabilities
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