1. Chapter 5 Class 10 Arithmetic Progressions
  2. Serial order wise
  3. Ex 5.3

Ex 5.3, 6 - Chapter 5 Class 10 Arithmetic Progressions

Last updated at May 29, 2018 by

Ex 5.3, 6 - The first and last term of AP are 17 and 350 - Ex 5.3

  1. Chapter 5 Class 10 Arithmetic Progressions
  2. Serial order wise

    3. Ex 5.3

    Examples →

Transcript

Ex 5.3 ,6 The first and the last term of an AP are 17 and 350 respectively. If the common difference is 9, how many terms are there and what is their sum? Given a = 17 , l = 350, d = 9 We need to find how many terms i.e. n and their sum i.e. Sn From (1) and (2) 367ร— ๐‘›/2 = ๐‘›/2 (25 + 9n) 367 = 25 + 9n 367 โ€“ 25 = 9n 342 = 9n 342/9 = n 38 = n n = 38 Now, we need to find sum Putting value of n in (1) Sum = 367 ร— ๐‘›/2 = 367 ร— 38/2 = 367 ร— 19 = 6973

Chapter 5 Class 10 Arithmetic Progressions
Serial order wise

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Davneet Singh is a graduate from Indian Institute of Technology, Kanpur. He has been teaching from the past 9 years. He provides courses for Maths and Science at Teachoo.