Answer: Choice B
mean = 13.1
median = 10.5
mode = 8
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Step-by-step explanation:
original data set = {8, 12, 14, 8, 9, 5, 17, 19, 31, 8}
sorted data set = {5, 8, 8, 8, 9, 12, 14, 17, 19, 31}
Sorting the data set is essential to finding the median
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To get the mean, we add up all the values and divide by 10
mean = (5+8+8+8+9+12+14+17+19+31)/10 = 131/10 = 13.1
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focus on the sorted set
sorted data set = {5, 8, 8, 8, 9, 12, 14, 17, 19, 31}
There are 10 items in the set. The middle most value will be exactly between slot 5 and slot 6, as these two slots are tied for the middle. In these slots are the values 9 and 12. They average to (9+12)/2 = 21/2 = 10.5, which is the median
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The mode is the most frequent or most occurring value. In this case, it would be 8 as it occurs the most times at three times.