Question

Find the sum of first 8 multiples of 3

Answer 1

3, 6,9.......
a = 3
d=3
n=8
by using formula Sn= n/2[2a+(n-1)d
=>8/2+[2×3(8-1)×3
=>4+6 (7×3)
108....

Answer 2

3 ,6 , 9, 12 .......24 a=3 , d= 3 S8 = 8/2 ( 2×3+(8-1)3). = 4(6+ 7×3).= 4(6+21) = 4(28) = 112