Question

2+6+10+14+........+30=

Answer 1

2 + 6 + 10 +14 +....+30 =
n = ( 30 - 2 ) : ( 6 - 2) +1
n = 28 : 4 +1
n = 7 +1
n = 8
S = [(30 +2) x 8] : 2
S = ( 32 x 8 ) : 2
S = 256 : 2
S = 128.