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3 years ago

12

In an examination there are four multiple choice questions with 3 options each, of which one option is the correct answer. In ho

w many ways can a student answer, such that he fails to answer all the four questions correctly? Thank you for help :)

1 answer:

mina [271]3 years ago

8 0

4 multiple choice questions
3 answers per question

4 × 3 = 12

<em>12 possible answers total</em>

12 - 4 = 8

<em>8 incorrect answers
</em><em>4 correct answers
</em><em>
</em>3 × 3 × 3 × 3 = 81
<em>
</em><em>81 possible ways they can answer
</em><em>
</em>Only one of those ways is 100% correct.
<em>
</em>81 - 1 = 80

80 ways

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