Home › SSC CGL › Quantitative Aptitude › number_system_lcm_hcf › The sum of the first 20 natural numbers is
The sum of the first 20 natural numbers is
A210
B220
C190
D200
Answer & Solution
Correct answer: A. 210
S_n = n(n+1)/2 = 20 x 21 / 2 = 210.
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