Mathematics
k + 2, 2k + 7 and 4k + 12 are the first three terms of an A.P. The first term of this A.P. is :
-2
0
2
3
AP GP
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Answer
Since,
k + 2, 2k + 7 and 4k + 12 are the first three terms of an A.P.
∴ 2k + 7 - (k + 2) = 4k + 12 - (2k + 7)
⇒ 2k - k + 7 - 2 = 4k - 2k + 12 - 7
⇒ k + 5 = 2k + 5
⇒ 2k - k = 5 - 5
⇒ k = 0.
⇒ k + 2 = 0 + 2 = 2.
Hence, Option 3 is the correct option.
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