allery2, ?, 12, 20, 30లో ఒక సంఖ్య దాచబడింది. ఆ దాచబడిన సంఖ్య ఏది?
A6
B8
C4
D10
Answer & Solution
Correct answer: A. 6
పదాలు n x (n + 1) రూపంలో ఉన్నాయి: 1x2, 2x3, 3x4, 4x5, 5x6, కాబట్టి రెండవ పదం 6.
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