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प्रश्न
If Ritu were younger by 5 years than what she really is, then the square of her age would have been 11 more than five times her present age. What is her present age?
उत्तर
Let the present age of Ritu be x years
(x − 5)2 = 5x + 11
x2 − 15x + 14 = 0½
(x − 14)(x − 1) = 0 ⇒ x = 1 or 14
x = 14 years ....(Rejecting x = 1 as in that case Ritu’s age 5 years ago will be – ve)
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