Q32 of 168 Page 7

Is the following situation possible? If so, determine their present ages. The sum of the ages of a mother and her daughter is 20 years. Four years ago, the product of their ages in years was 48.

Let the mother age be ‘X’ years, then her daughter’s age will be ‘(20–X)’ years.


As per the question,


(X – 4)(20 – X – 4) = 48


(X – 4)(16 – X) = 48


16X – 64 – X2 + 4X = 48


–X2 + 20X – 112 = 0


X2 – 20X + 112 = 0


On applying Sreedhracharya formula






it does not have real values, then it is not possible for the above situation to happen.


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