Mathematics
The sum of first 30 odd natural numbers is:
800
900
729
1249
AP
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Answer
1, 3, 5, 7, ……, 30th term.
The odd natural numbers form an Arithmetic Progression (A.P.) :
a = 1
d = 3 - 1 = 2
n = 30
We know that,
Sn = [2a + (n - 1)d]
⇒ S30 = [2(1) + (30 - 1)2]
= 15[2 + (29)2]
= 15[2 + 58]
= 15 × (60)
= 900.
Hence, option 2 is the correct option.
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