Question

find the sum of
the sum of first 25 terms of
the
AP 6,12, 18,24
​

Answer 1

Answer:

use the formula of sum of nth term

Step-by-step explanation:

Sn = n/2 +(n-1) d

Answer 2

Answer:

Step-by-step explanation:

Concept :  $S_{n} = \frac{n}{2} [ 2a + (n - 1)d]$  

                where, Sₙ = Sum of AP series

                             n = number of terms in AP

                             a = first element of AP

                             d = common difference

Solution :

Given AP Series, 6, 12, 18, 24

then, a = 6, d = 6 , n= 4

∴ $S_{4} = \frac{4}{2}[2 * 6 + (4 - 1) * 6 ]$

⇒ $2*[12 + 18]$ = 60

∴ Sum of the AP series is 60

#SPJ3