Start learning →

What is the SUM of the first 10 natural numbers (1 + 2 + 3 + … + 10)?

A45
B50
C55
D60
Answer & Solution
Correct answer: C. 55
Sum of first n natural numbers = n(n+1)/2. For n = 10: 10 × 11 / 2 = 55. (This is also the 10th triangular number.)
Practise this question with Quill — CBSE Class 9 →

Keep practising Sequences and Progressions

Browse all Sequences and Progressions questions for CBSE Class 9, or explore more Mathematics topics.

Start a Sequences and Progressions lesson →
Related questions
Complete the progression rulesSequence numbersAP or GP?The sequence 240, 280, 320 is an AP with common difference:Is 1, -1, 1, -1 a geometric progression?A rule that uses the previous two terms builds which sequence?The fifth triangular number, 15, equals:The sum of the first n natural numbers is: