Question

calcule a soma do termo da P.A. (10,16,22...70)

Answer 1

a1=10, a2=16, a3=22, a4=28, a5=34, a6=40, a7=46, a8= 52, a9= 58, a10=64, a11=70.

S11= (a1+a11).n/2
S11= (10+70).11/2
S11= 440