Quantitative Aptitude • Ratio, Average & MixtureEasy
What is the average of the first 39 odd numbers?
A. 39✓ Correct Answer
B. 19.5
C. 40
D. 77
💡 Solution & Explanation
The sum of the first n odd numbers is n², so here it is 39² = 1521. Average = 1521 ÷ 39 = 39. For any evenly spaced list, the average is also the middle of the first and last numbers.
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