If there are where multiple-choice questions on an exam, each having four possible answers, how many different sequences of answers are there?

**Solution:-**

If any one of k different mutually exclusive and collectively exhaustive events can occur on each of n trials, the number of possible outcomes is equal to k^{n}.

The four possible answers to each multiple-choice question are mutually exclusive and collectively exhaustive. There are twelve questions.

K = 4 and n = 12

Substitute 4 for k and 12 for n in the expression k^{n} and simplify.

k^{n} = 4^{12}

=16777216

There are 16777216 different square of answers.