Mathematics
The sum of first 40 positive integers divisible by 6 is :
2460
3640
4920
4860
AP
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Answer
Sequence :
6, 12, 18, ……., upto 40th term.
The above sequence is an A.P. with,
a = 6
d = 6
n = 40
We know that,
Sn = [2a + (n - 1)d]
⇒ S40 = [2(6) + (40 - 1)6]
= 20[12 + (39)6]
= 20(12 + 234)
= 20 × (246)
= 4920.
Hence, option 3 is the correct option.
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