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The math test has 10 multiple choice questions, each with 4 answers. If Betty guesses correctly on the first 2 questions, what is the probability that she will guess correctly on the third question?

User Archaelus
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2 Answers

1 vote

Answer: The probability that she will guess correctly on the third question
=(1)/(4)


Explanation:

Given: The math test has 10 multiple choice questions, each with 4 answers.

To find probability that she will guess correctly on the third question, we need to just look at only one question which has 4 options and one of them is the right answer, thus probability of choosing the right answer from 4 option is the fraction of 1 over 4.

The probability that she will guess correctly on the third question


=\frac{\text{answer of a question}}{\text{total options of a question}}


=(1)/(4)

User Emrass
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2 votes
It doesn't matter that she guessed correctly on the first two questions, guessing the third question correctly is independent of guessing any other question correctly. Therefore, the probability is one out of four, 1/4.
User Raviraj Jadeja
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7.4k points