There are 15 scouts and Ron wants to make sure they each get 2 s'mores a piece, for a total of 15*2 = <<15*2=30>>30 s'mores
1 chocolate bar can make 3 s'mores and he wants to have enough for 30 s'mores, so he needs 30/3 = <<10=10>>10 chocolate bars
Each chocolate bar costs $1.50 and he needs 10, for a total of 1.5*10 = $<<1.5*10=15.00>>15.00
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