Question

Interpole 6 meios aritméticos entre 4 e 81 (conta resolvida por favor!)

Answer 1

P.A.(4,A 2 , A 3 ,A 4 , A 5 , A 6 ,A 7 , 81)
a 8 = 81
a 8 = a 1 + (n - 1 ).r
a 8 = 4 + (8 - 1 ) . r
81 - 4 = 7 r
77 = 7 r
77/7 = r
r = 11
a 2  = a 1 + r
a 2 = 4 + 11 = 15
a 3 = a 2 + 11
a 3 = 15 + 11 = 26
a 4 = a 3 + r
a 4 = 26 + 11
a 4 = 37
a 5 = a 4 + r
a 5 =37 + 11
a 5 = 48
a 6 = a 5 + 11
a 6 = 48 + 11 = 59
a 7 = a 6 + 11 = 59 + 11 = 70
a 8 = a 7 + 11
a 8 = 70 + 11 = 81

P.A.(4,15,26,37,48,59,70,81)