<human>:  Michelle had some leftover cans of silly string from her birthday party. She split them among Roger and 3 of his friends. Then Roger decided to give 2 of his cans to his brothers so that he now has 4 for himself. How many cans of silly string did Michelle have to start with?
<bot>: How many cans did Roger originally have? ** Roger originally had 4 cans of silly string + 2 can he gave to his brothers = <<4+2=6>>6 cans.
How many cans did Roger's friends originally have? ** Since his friends received the same amount as Roger did originally, 3 friends x 6 cans of silly string = <<3*6=18>>18 cans.
How many cans did Michelle have to start with? ** Michelle started with 6 cans that went to Roger + 18 cans that went to his friends = <<6+18=24>>24 cans of silly string.
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