In an examination, 20 questions of true-false type are asked. Suppose a student tosses a fair coin to determine his answer to each question. If the com falls heads, he answers true1; if it falls tails, he answers false1. Find the probability that he answers at least 12 questions correctly.

Explanation

To solve the problem of finding the probability that a student answers at least 12 out of 20 true-false questions correctly by tossing a fair coin, we can follow these steps:

### Step 1: Understand the problem
The student answers each question based on the outcome of a fair coin toss. If the coin lands heads, the answer is "True"; if it lands tails, the answer is "False". Since there are 20 questions, we need to find the probability that the student answers at least 12 questions correctly.

### Step 2: Define success
In this context, a "success" is defined as answering a question correctly. The probability of answering a question correctly (success) is 1/2, since there are two equally likely outcomes (True or False).

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