What is the SUM of the first 10 natural numbers (1 + 2 + 3 + … + 10)?
A45
B50
C55
D60
Answer & Solution
Correct answer: C. 55
Sum of first n natural numbers = n(n+1)/2. For n = 10: 10 × 11 / 2 = 55. (This is also the 10th triangular number.)
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