What is the sum of the first (83) natural numbers?
Answer and explanation
Correct answer: 3486
The sum of the first \(n\) natural numbers is \(S_n=\frac{n(n+1)}{2}\). Therefore, \(S_{83}=\frac{83\times84}{2}=83\times42=3486\). Hence, option B is correct. Option A is close to the sum up to \(82\), while the other values do not follow from the formula. Exam tip: use \(n(n+1)/2\) for the sum of consecutive natural numbers from 1 to \(n\).
Frequently asked questions
What is the correct answer to this question?
3486
Why is this the correct answer?
The sum of the first \(n\) natural numbers is \(S_n=\frac{n(n+1)}{2}\). Therefore, \(S_{83}=\frac{83\times84}{2}=83\times42=3486\). Hence, option B is correct. Option A is close to the sum up to \(82\), while the other values do not follow from the formula. Exam tip: use \(n(n+1)/2\) for the sum of consecutive natural numbers from 1 to \(n\).
Which subject and chapter does this question cover?
This is a Class 9 Mathematics question. Chapter: Sequences and Progressions. Topic: Sum of first n natural numbers.
Student feedback
Was this question useful?
👍 0 Helpful 👎 0 Not helpful
Yes 0% No 0%
0 responsesStudent Reviews
No published reviews yet.
