A man recently bought two aeroplanes, but afterwards found that they would not answer the purpose for which he wanted them. So he sold them for £600 each, making a loss of 20 per cent. on one machine and a profit of 20 per cent. on the other. Did he make a profit on the whole transaction, or a loss? And how much?
9.--THE TWO AEROPLANES.
From Amusements in Mathematics by Henry Ernest Dudeney.
