T2 = 4, T4 = 16 Tx = arn-1 T2 = ar2-1 = 4 i.e. ar3 = 16, i.e. ar = 4 T4 = ar4-1 therefore, \(\frac{T_4}{T_r}\) = \(\frac{ar^3}{ar}\) = \(\frac{16}{4}\) r2 = 4 and r = 2 but ar = 4 a = \(\frac{4}{r}\) = \(\frac{4}{2}\) a = 2 Sn = \(\frac{a(r^n - 1)}{r - 1}\) S5 = \(\frac{2(2^5 - 1)}{2 - 1}\) = \(\frac{2(32 - 1)}{2 - 1}\) = 2(31) = 62