Iris’ family is planning a surprise birthday party for her. The party will include her 3 uncles and 4 aunts who have a son and daughter each as well as her brother and mother. In total, how many people are coming to Iris’ birthday party?
Use reasoning to answer the following question.
23
Each of her aunts and uncles have a family unit of 1 son + 1 daughter + 1 aunt / uncle = 3 people.

Iris has a total of 3 uncles + 4 aunts = 7 aunts or uncles in these family units.

So among her aunts, uncles, and cousins, there will be 7 family units * 3 people in each family unit = 21 people.

Including her mother and brother, there will be a total of 21 people + 1 mother + 1 brother = 23 people coming to her party.

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So, the answer is 23