Carlo puts tins into small boxes and into large boxes. He puts 6 tins into each small box.
He puts 20 tins into each large box.
Carlo puts a total of 3000 tins into the boxes so that number of tins in small boxes : number of tins in large boxes = 2 : 3

Carlo says that less than 30% of the boxes filled with tins are large boxes.

Is Carlo correct?
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