In 15 years she will be twice as old as her son.How old is she now?

题目

In 15 years she will be twice as old as her son.How old is she now?
good

答案

If her son is 5,she is 25.
If her son is 6,she is 27.
If her son is 7,she is 29.
If her son is 8,she is 31.
If her son is 9,she is 33.
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