nth term of an AP
Sequences, series and the binomial theorem · Mathematics
Study notes
Q: Find the 15th term of 7, 12, 17, ... Which term is 97? Step 1: a = 7, d = 5. Step 2: T₁₅ = 7 + 14×5 = 7 + 70 = 77. Step 3: Set Tₙ = 97: 7 + (n-1)5 = 97 → (n-1)5 = 90 → n - 1 = 18 → n = 19. So 97 is the 19th term.