Insert five numbers between 8 and 26 such that the resulting sequence is an arithmetic progression.
8A1, A2, A3, A4, A5, 26
a = 8, n = 7, an = 26, d = ?
an = a + (n-1)d ⇒ 26 = 8 + (7 – 1)d = 26 – 8 = 6d
18 = 6d ∴ d=3
Common difference
∴ A1 = a + d = 8 + 3 =11, A2 =11 + 3 = 14, A3 = 17, A4 = 20, A5 = 23 are the 5 AM’*
