Quantitative Aptitude • Ratio, Average & MixtureEasy
What is the average of the first 13 natural numbers?
A. 13
B. 7✓ Correct Answer
C. 6.5
D. 14
💡 Solution & Explanation
The sum of the first n natural numbers is n(n + 1)/2 = 13 × 14 ÷ 2 = 91. Average = 91 ÷ 13 = 7. For any evenly spaced list, the average is also the middle of the first and last numbers.
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