Question 1056532
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sonu's grandmother is 80 years old and sonu is 20 year old . how many years ago was his grandmother 7 times as old as sonu ?
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80-x = 7*(20-x),


80-x = 140 - 7x,


7x - x = 140 - 80,


6x = 60,


x = 10.


<U>Answer</U>.  10 years ago.  (They were 10 and 70 years old).