

InterviewSolution
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The sum of squares of two consecutive even natural numbers is 244; find the numbers. |
Answer» Let the first even natural number be x. ∴ the next consecutive even natural number will be (x + 2). According to the given condition, x2 + (x + 2)2 = 244 ∴ x2 + x2 + 4x + 4 = 244 ∴ 2x2 + 4x + 4 – 244 = 0 ∴ 2x2 + 4x – 240 = 0 ∴ x2 + 2x – 120 = 0 …[Dividing both sides by 2] ∴ x2 + 12x – 10x – 120 = 0 ∴ x(x + 12) – 10 (x + 12) = 0 ∴ (x + 12) (x – 10) = 0 By using the property, if the product of two numbers is zero, then at least one of them is zero, we get ∴ x + 12 = 0 or x – 10 = 0 ∴ x = -12 or x = 10 But, natural number cannot be negative. ∴ x = 10 and x + 2 = 10 + 2 = 12 ∴ The two consecutive even natural numbers are 10 and 12. |
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