Lessons

General Aptitude
9.1 Numbers - General Questions

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Q.

The sum of first 45 natural numbers is:

View Answer

Correct choice: A

Explanation:

Let Sn = (1 + 2 + 3 + ... + 45)

This is an A.P. in which a = 1, d = 1, n = 45 and l = 45

∴Sn = n (a + l) = 45 x (1 + 45)   = (45 x 23)   = 1035
2 2

Required sum = 1035.

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