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What is the probability of rolling a number which is divisible by two on a fair die?
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A fair die is a cube with six faces.
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They are numbered one, two, three, four, five, and six.
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The probability of an event occurring can be written as a fraction, where the numerator is the number of successful outcomes and the denominator is the number of possible outcomes.
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In this case, the number of successful outcomes are all of those that are divisible by two.
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All even numbers are divisible by two.
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The even numbers on a die are two, four, and six.
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Therefore, all three of these are divisible by two.
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As there are three numbers that are divisible by two, our numerator, the number of successful outcomes, is three.
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The denominator is equal to six as there is six possible outcomes on a die.
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This fraction can be simplified by dividing the numerator and denominator by three.
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Three divided by three is equal to one, and six divided by three is equal to two.
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This means that the probability of rolling a number which is divisible by two on a fair die is one-half or one out of two.