Q15 of 85 Page 110

If 2k + 1, 13, 5k — 3 are three consecutive terms of A.P., then k = ……….

If 2k + 1, 13, 5k — 3 are three consecutive terms of A.P., then,


⇒ 13 – (2k + 1) = (5k – 3 ) – 13 …..(common difference)


⇒ 12 – 2k = 5k – 16


⇒ 28 = 7k


⇒ k = 4


∴ correct option is (c).

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