The sum formula is n(n + 1) / 2 > 1000, so n(n + 1) > 2000. Testing values gives 44 x 45 / 2 = 990 and 45 x 46 / 2 = 1035, so smallest n is 45.
Find the smallest value of n such that the sum of the first n natural numbers is greater than 1,000.
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The sum of the first n natural numbers is given by:
Sn = n(n + 1) / 2
We need the smallest n such that:
n(n + 1) / 2 > 1000
n(n + 1) > 2000.
Since 44 x 44 = 1936 and 45 x 45 = 2025,
let us check consecutive integers near 44:
For n = 44:
S44 = 44 x 45 / 2 = 22 x 45 = 990 (less than 1000).
For n = 45:
S45 = 45 x 46 / 2 = 45 x 23 = 1035 (greater than 1000).
Thus, the smallest value of n is 45.
For more NCERT Solutions of Class 9 Ganita Manjari Chapter 8 Predicting What Comes Next: Exploring Sequences and Progressions Question Answer (2026-27)
https://www.tiwariacademy.com/ncert-solutions/class-9/maths/ganita-manjari-chapter-8/