Question

Insira 7 meios aritmeticos entre 3 e 75 ?

Answer 1

a1=3
an=75
n=9
r=?

an=a1+(n-1)r
75= 3+(9-1)r
75-3=8r
72=8r
72/8=r
9=r

PA=(3,12,21,30,39,48,57,66,75)