Discussion
If the sum of the first 20 consecutive positive odd numbers is divided by \(20^{2}\), the result is
Answer: A
The result is 1.
The sum of the first \(n\) odd numbers is \(n^{2}\): \(1 + 3 + 5 + \cdots + (2n - 1) = n^{2}\). For \(n = 20\) the sum is 400, and \(400/20^{2} = 1\).
Equivalently, the 20 odd numbers from 1 to 39 have average \((1 + 39)/2 = 20\), so their sum is \(20 \times 20\). The options 20, 2 and 1/2 come from dividing by 20 instead of \(20^{2}\) or from miscounting the terms.
No comment is present. Be the first to comment.
Loading…
Post your comment
Please log in or register to post a comment.
Examination Categories
- SSC Exams
- Banking Exams
- Teaching Exams
- Civil Services Exams
- Railways Exams
- Engineering Recruitment Exams
- Defence Exams
- State Government Exams
- Police Exams
- Insurance Exams
- Nursing Exams
- Other Government Exams
- NRA CET
- PG Entrance Exams
- Campus Placement
- MBA Entrance Exams
- CUET and UG Entrance
- Judiciary Exams
- Regulatory Body Exams
- Software Development