Question

Insira sete meios aritméticos entre 3 e 27.

Answer 1

a 1 = 3
a 9 = 27
n = 9
a 9 = a 1 + (n - 1 ) .r
a 9 = 3 + (9 - 1 ). r
27 = 3 + 8 r
27 - 3 = 8 r
24 = 8  r
24/8 = r
 r = 3
a 2 = a 1 + r ⇒ 3 + 6 = 6
a 3 = a 2 + r ⇒6 + 3 = 9
a 4 = a 3 + r  ⇒9 + 3 = 12
a 5 = a 4 + r ⇒12 + 3 = 15
a 6 = a 5 + r ⇒15 + 3 = 18
a 7 = a  6 + r ⇒18 + 3 = 21
a  8 = a 7 + r ⇒ 21 + 3 = 24
a 9 = a 7 + r ⇒ 24 + 3 = 27
P.A.(3,6,9,12,15,18,21,24,27)