Question

what is the sum of the first 20 terms of. an ap if a=4 and t20 =4
A)40
B)200
C)400
D)800​

Answer 1

Answer:

i think its option D)800

Answer 2

Step-by-step explanation:

Given What is the sum of the first 20 terms of. an A.P if a = 4 and t20 = 4

• So to find the sum of first n terms of the series we have
•                                     Sn = n(a1 + an) / 2
• where n is the number of terms, a1 is the first term and an is the last term
• Substituting these terms we get
•              So  S20 = 20 (4 + 4) / 2
•                          = 20 x 8 / 2
•                            = 80

Reference link will be

https://brainly.in/question/33283416