Question

A=5 d=3 an=50 find n and 5n

Answer 1

a=5
d=3
an=50
an =a+(n-1)d=50
5+(n-1)3=50
(n-1)3=50-5
(n-1)3=45

n-1=45/3

n-1=15

n=15+1

n=16