<human>:  Emma can make and upload 72 vlogs per month. But she was only able to make 18 vlogs for the first week, 21 vlogs for the second week, and 15 vlogs for the third week. How many vlogs should she do to complete the 72 vlogs per month?
<bot>: How many vlogs did Emma make? ** Emma was able to make 18 + 21 + 15 = <<18+21+15=54>>54 vlogs for 3 weeks.
How many more vlogs does Emma need to do? ** Therefore, Emma needs to do 72 - 54 = <<72-54=18>>18 more vlogs to complete the 72 vlogs.
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