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If k, 2k- 1 and 2k + 1 are three consecutive terms of an A.P., the value of k is

(A) 2

(B) 3

(C) -3

(D) 5

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#### Solution

Correct answer: B

k, 2k - 1, 2k + 1 are in Arithmetic Progression

if a_{1}, a_{2} and a_{3} are in A.P. then

a_{2} –a_{1} = a_{3} – a_{2}

2a_{2} = a_{3} + a_{1}

2 x (2k - 1) = (2k +1) + k

4k - 2 = 3k +1

k = 3

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