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本文在初中知识学习范围内,举例介绍古今中外数学家巧解应用题的若干技巧,供学生学习时参考。一、张广厚巧解三人百岁问题赵、钱、孙三人年龄之和是100岁,赵28岁时,钱的年龄是孙的两倍;钱20岁时,赵的年龄是孙的三倍,问三人年龄各是多少?解:设赵、钱、孙现在的年龄分别为x岁、y岁、z岁,又设a年前赵28岁,则有y-a=2(z-a)。∵x+y+z=100,∴a年前,有28+(y-a)+(z-a)=
In this paper, junior high school knowledge in the context of learning, an example of ancient and modern mathematicians at home and abroad clever solution to some of the skills problems for students to learn reference. First, Zhang Guanghou cleverly solve the three-year-old problem Zhao, Qian, Sun three age is 100 years old, Zhao 28 years old, the age of money is twice the Sun; money 20 years old, Zhao’s age is Sun’s three Times, ask each three age how much? Solution: Set Zhao, money, grandchildren are now age x, y years old, z years, and set a year ago Zhao 28 years old, then ya = 2 (za). ∵x + y + z = 100, ∴a years ago, there are 28+ (y-a) + (z-a) =