一道英文数学提!janet is three times as old as her daughter,mary.five years ago jant was four times
题目
一道英文数学提!janet is three times as old as her daughter,mary.five years ago jant was four times
janet is three times as old as her daughter,mary.five years ago jant was four times as old as mary .how old is janet now?how old will mary be in 7 years'time
答案
Suppose Mary is x years old now.Then
4*(x-5) = 3x-5
Solve it,get x = 15
So Janet is 3x = 45 years old now and Mary will be 22 years old in 7 years' time.
举一反三
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我想写一篇关于奥巴马的演讲的文章,写哪一篇好呢?为什么好
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