Adv
Rajan@2021
  • 0
Guru

Which term of the AP 20, 19 1/2, 18 1/2, 17 3/4,….us its first negative term?

  • 0

One of the most important question from arithmetic progression chapter in which we have been given a series of AP 20, 19 1/2, 18 1/2, 17 3/4 and we have to find its first negative term?

Book RS Aggarwal, Class 10, Arithmetic Progression, chapter 5A, question no 25.

Share

1 Answer

  1. 20,19 1/4​, 18 1/2​,....
    or 20,77​/4,37/2​,....
    a=20
    d=77​/4−20=−3/4​
    Let nth term of A.P. be first negative term
    So, 20+(n−1)(4−3​)<0
    ⇒80−3n+3<0
    ⇒3n>83
    ⇒n>27 2/3​
    Hence, 28th term is first negative term.

    • 0
Leave an answer

Leave an answer

Browse

Choose from here the video type.

Put Video ID here: https://www.youtube.com/watch?v=sdUUx5FdySs Ex: "sdUUx5FdySs".

Captcha Click on image to update the captcha.

Related Questions