Question

i solved this activity... may be last answer is 2420 ..... please tell me this answer is correct?
OR
2380 correct answer ?​

Answer 1

Answer:

Step-by-step explanation:

The series is 4, 8, 12, 16, 20 ........136 which are in AP

a = 4, d = 4, tₙ = 136

nth term is given by tₙ = a + (n - 1)d

=> 136 = 4 + (n - 1)4

=> 136 = 4 + 4n - 4

=> 136 = 4n

=> n = 34.

Sum of n terms of AP, Sₙ = n/2 [2a +  (n - 1 )d]

S₃₄ = 34/2[2*4 + (34 - 1 )4]

       = 17 [8 + 132]

        = 17 * 140

         = 2380.                                

Answer 2

2380 is your correct answer..

hope this image will help you...