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标题: Solving System Equation [打印本页]

作者: 华盛屯 时间: 2008-11-18 05:23
标题: Solving System Equation

Given the system of equations

49x-14y+21z=40

14x+70y+28z=43

42x-14y-14z=11

What is x+y+z ?

Answer: 3/2

This is a math competition question, and you are only given 1.5 minute to solve. You can solve x, y, z in a hard way, it will take long time and easyly make mistake. I think there might be a trick however I could not figure out.

作者: yma16 时间: 2008-11-25 07:09
标题: I do not think there is a short cut.

if calculator is allowed, you can solve it in a minute.

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