A.P is known for Arithmetic Progression whose common difference = a_n – a_n-1 where n > 0

a = a₁ = 1, a₂ = 4, l = 88

Common difference, d = a₂ – a₁ = 4 – 1 = 3

We know, n^th term from end, b_n = l – (n – 1)d where l is last term or a₁ and d is common difference and n is any natural number

∴ b₁₂ = 88 – (12 – 1)3

⇒ b₁₂ = 88 – 36 + 3

⇒ b₁₂ = 91 – 36

⇒ b₁₂ = 55

Hence, 12^thterm from end for the given A.P is 55