<human>:  A farmer has 900 eggs. He placed them on a tray, which holds 30 eggs each. How much will the farmer earn if he sells it for $2.5 per tray?
<bot>: How many trays are there? ** There are 900 / 30 = <<900/30=30>>30 trays that hold 900 eggs.
How much will the farmer earn if he sells it for $2.5 per tray? ** So, the farmer will earn 30 x $2.5 = $<<30*2.5=75>>75 if he sells it per tray.
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