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The scores earned on a math test are 86, 80, 76, 68, 73, 85, 74, 70, 71, and 70.
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Find the mean, median, and mode for the set of data.
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We recall that in order to calculate the mean from a data set, we firstly need to add all the values.
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In this question, this is the sum of the scores in the test.
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We then need to divide this total by the number of values, in this case, 10.
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The sum of the scores is 753.
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753 divided by 10 is 75.3.
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This means that the mean of the scores is 75.3 marks.
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We can calculate the median by finding the middle value.
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Before doing this, we must order the numbers from smallest to largest or largest to smallest.
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In ascending order, the scores are 68, 70, 70, 71, 73, 74, 76, 80, 85, and 86.
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As they are an even number of values, in this case, 10, there will be two middle numbers.
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These are 73 and 74.
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The median will be the value halfway between these two numbers, or the mean of the two numbers.
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This is equal to 73.5.
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Therefore, the median score is 73.5.
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The mode is the most frequently occurring value or values in our data set.
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In this question, eight of the values appear once, and 70 appears twice.
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As 70 occurs more often than any other data value, the mode of the scores is 70.
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This set of data has a mean of 75.3, a median of 73.5, and a mode of 70.