Kareem cannot decide which of two washing machines to buy. The selling price of each is ​$550. The first washing machine is marked down by 40​%. The second washing machine is marked down by 30​% first and then an additional 10​% off. Find the sale price of each washing machine. Use pencil and paper. Explain why Kareem should buy the first washing machine rather than the second if the machines are the same except for the selling price.