The number of terms in the series 1 + 3 + 5 + 7 + …. + 73 + 75 is :

The number of terms in the series 1 + 3 + 5 + 7 + …. + 73 + 75 is :
[A]30
[B]36
[C]38
[D]28

38
Let the number of terms be n.
It is an Arithmetic Series whose first term, a = 1 and common difference d = 2.
∴ nth term = a + (n – 1) d
=> 75 = 1 + (n - 1) 2
=> 2 (n - 1) = 74
=> n - 1 = \frac{74}{2} = 37
=> n = 37 + 1 = 38
Hence option [C] is the right answer.

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