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If Σn = 36, find n

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DSSSB Pharmacist 2014: Previous Year Paper
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  1. 9
  2. 8
  3. 6
  4. 10

Answer (Detailed Solution Below)

Option 2 : 8

Detailed Solution

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Given:

Σn = 36

Formula used:

Σn = n(n + 1) / 2

Where,

Σn = sum of the first n natural numbers

Calculation:

Σn = 36

We need to find n such that

n(n + 1) / 2 = 36

⇒ n(n + 1) = 72

⇒ n2 + n - 72 = 0

⇒ (n - 8) (n + 9) = 0

Taking the positive value, n - 8 = 0 

So, n = 8

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Last updated on Mar 27, 2025

-> The DSSSB Pharmacist Exam for Advt. No. 04/2024 will be held from 5th to 7th May 2025.

-> DSSSB Pharmacist Notification was released for 2 vacancies (Advt. No. 05/2024), and 318 vacancies (Advt. No. 01/2024)

-> Candidates with a Bachelor's degree in Pharmacy are eligible to apply for the post.

-> The selection process includes a written test (One Tier Technical Examination) for 200 marks.

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