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प्रश्न
The product of a girl's age five years ago and her age 3 years later is 105. Find her present age.
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उत्तर
Let the present age of the Girl be G year. Then, as per the question description,
(G - S)(G + 3) = 105
⇒ G2 - 2G - 120 = 0
⇒ G2 -12G + 10G - 120 = 0
⇒ G (G - 12) +10 (G - 12) = 0
⇒ G=12 , G = -10 (Agecannotbe negative)
⇒ G=12 Years
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