Question
Sum of squares of three consecutive numbers is 1730.
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 = 1730 => x2 – 2x + 1 + x2 + x2 + 2x + 1 = 1730 => 3x2 = 1730 - 2 => x2 = 1728/3 => x2 = 576 => x = 24 Required sum = (24 – 1) + (24 + 1) = 48
24, 42, 60, ?, 96, 114
What will come in place of (?) question mark in the given number series.
10, 17, 26, 37, 50, ?
660, 653, 639, 618, 590, ?
What will come in place of the question mark (?) in the following series?
75, 219, 388, ?, 809, 1065168, 178, ?, 273, 400, 618, 963
60   61    57   66    ?      75    39
...What will come in place of the question mark (?) in the following series?
2, 5, 14, 41, 122, 365, ?
81, 83, 87, 95, 111, ?
What will come in place of the question mark (?) in the following series?
400, 841, 1202, ?, 1716, 1885
64, 66, 69, 74, 81, ?