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Received: 150 widgets at $1 each.
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Received: 130 widgets at $2 each.
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S 145
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Received: 50 widgets at $2.5 each.
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S 75
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S 180
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Received: 50 widgets at $4 each.
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Received: 30 widgets at $5 each.
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Received: 40 widgets at $5.5 each.
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Promotion: 30% discount for next 2 buying customers
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S 50
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S 30
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Received: 50 widgets at $6 each.
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Received: 265 widgets at $10 each.
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