数学题:甲乙两种皮鞋的原价相同，换季时，甲种皮鞋按五折优惠，乙种皮鞋按四折销售。李老师用216元买了这两种皮鞋，求每双鞋鞋的原价是多少？

数学题解答：由于两种皮鞋原价相同，所以可以设每双皮鞋原价是x元。这样用方程解答的过程就是：

甲皮鞋一双的价钱　+　乙皮鞋一双的价钱　＝　216

50%x + 40%x =216

0.9x = 216

x = 240

答：每双皮鞋原价是240元。

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