Question 1090375
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The original set is L1 = {23,34,55,77,56,34,55,80,23}

Sort the values from smallest to largest to get L2 = {23, 23, 34, 34, 55, 55, 56, 77, 80}


Let's make a frequency table for all the values
<table border=1 cellpadding=3><tr><th>Value</th><th>Frequency</th></tr><tr><td>23</td><td>2</td></tr><tr><td>34</td><td>2</td></tr><tr><td>55</td><td>2</td></tr><tr><td>56</td><td>1</td></tr><tr><td>77</td><td>1</td></tr><tr><td>80</td><td>1</td></tr></table>


The largest frequency is 2 and it happens for the values 23, 34 and 55. Therefore the mode is the set <font color=red size=4>{23, 34, 55}</font>


Note: it is possible to have more than one mode which is why I used curly braces to indicate set notation.
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