First, order the number set from least to greatest:
3 , 4 , 4 , 7 , 8 , 9 , 12 , 14 , 16 , 20
Mean: You find the mean by combining all the terms, and dividing by the amount of the terms there are in the number set:
(3 + 4 + 4 + 7 + 8 + 9 + 12 + 14 + 16 + 20)/10
(97)/10 = 9.7
Mean: 9.7
Median: You find the median by first ordering the number set from least to greatest, and finding the middle number. Note that if there is a even number of numbers in the set, you find the mean with the two given median digits:
8 & 9 are the median numbers:
(8 + 9)/2 = (17)/2 = 8.5
Median: 8.5
Mode: The mode is the number(s) in the set that shows up the most:
Mode: 4 (shows up one more time than all other numbers)
Range: The range can be found by subtracting the least number from the greatest number in the number set:
Range: 20 - 3 = 17
Range: 17
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