Adv
AnilSinghBora
  • 0
Guru

Find the sum of first 51 terms of an AP whose second and third terms are 14 and 18, respectively. Q.8

  • 0

For class 10th math of arithmetic progressions of exercise 5.3 of math, how i solve this important question in easy way, Find the sum of first 51 terms of an AP whose second and third terms are 14 and 18, respectively.

Share

1 Answer

  1. Given that,

    Second term, a2 = 14

    Third term, a3 = 18

    Common difference, d = a3a2 = 18−14 = 4

    a2 = a+d

    14 = a+4

    a = 10 = First term

    Sum of n terms;

    Sn = n/2 [2a + (n – 1)d]

    S51 = 51/2 [2×10 (51-1) 4]

    = 51/2 [2+(20)×4]

    = 51 × 220/2

    = 51 × 110

    = 5610

    • -1
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