Use the stem and leaf plot graph to answer the question.
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Explanation:
Count the number of leaves marked in green.
There are 2+3+5+3 = 13 leaves total. This represents tickets were sold on 13 days.
Each stem and leaf combines to form a different ticket count. For instance, the stem of 1 and leaf of 8 combine to get the value 18. So 18 tickets were sold on that particular day.