Carl has been selling watermelons on the side of the road for $3 each. This evening he went home with $105 in profit and 18 watermelons. How many watermelons did he start out with this morning?
Carl sells his watermelons for $3 each so today he sold $105 / $3 per watermelon = <<105/3=35>>35 watermelons.
He had 18 watermelons left over, so this morning he started with 18 + 35 = <<18+35=53>>53 watermelons.
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