What remains after subtracting (1000) from the sum of the first (50) natural numbers?
Answer and explanation
Correct answer: 275
The sum of the first 50 natural numbers is
\(S=\frac{50\times51}{2}=1275\). Therefore, after subtracting 1000, we get \(1275-1000=275\). Hence, option D is correct. A value such as 255 results from an error in finding the sum or carrying out the subtraction. Exam tip: use \(\frac{n(n+1)}{2}\) for the sum of the first \(n\) natural numbers.
Frequently asked questions
What is the correct answer to this question?
275
Why is this the correct answer?
The sum of the first 50 natural numbers is
\(S=\frac{50\times51}{2}=1275\). Therefore, after subtracting 1000, we get \(1275-1000=275\). Hence, option D is correct. A value such as 255 results from an error in finding the sum or carrying out the subtraction. Exam tip: use \(\frac{n(n+1)}{2}\) for the sum of the first \(n\) natural numbers.
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.
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