Arithmetic Progression(AP)

In an Arithmetic Progression (A.P.) the fourth and sixth terms are 8 and 14 respectively. Find the : (i) first term (ii) common difference (iii) sum of the first 20 terms

Let b_i > 1 for i =1, 2,....,101. Suppose log_e b_1, log_e b_2,....,log_e b_101 are in Arithmetic Progression (A.P.) with the common difference log_e 2 . Suppose a_1, a_2,...,a_101 are in A.P. such that a_1 = b_1 and a_51 = b_51 . If t = b_1 + b_2+.....+b_51 and s = a_1+a_2+....+a_51 then