Question
Sum of squares of three consecutive numbers is 677. Find
the sum of first and third number.Solution
Let the numbers be (x – 1), x and (x + 1) => (x – 1)2 + x2 + (x + 1)2 = 677 => x2 – 2x + 1 + x2 + x2 + 2x + 1 = 677 => 3x2 = 677 - 2 => x2 = 675/3 => x2 = 225 => x = 15 Required sum = (15 – 1) + (15 + 1) = 30
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