WEBVTT
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A box contains five red marbles, eight green marbles, and four yellow marbles.
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If a marble is picked from the box at random, what is the probability that the marble is red?
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We are told in the question that we have five red marbles.
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There are eight green marbles.
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And finally, we have four yellow marbles.
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This means that we have 17 marbles in total, as five plus eight plus four equals 17.
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We are also told that a marble is selected at random.
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This means there is an equal chance of selecting each of the 17 marbles.
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We know that probability can be written as a fraction: the number of successful outcomes over the number of possible outcomes.
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In this question, we are trying to calculate the probability that the marble is red.
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As there are five red marbles in the box, the number of successful outcomes is five.
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The number of possible outcomes is 17 as there are 17 marbles in total.
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The probability of picking a red marble from the box is five out of 17 or five seventeenths.