In a geometric progression the fourth term is 80 and the ninth term is 2560
MATHEMATICS · Subjective · CBSE · Mathematics · Sequences and Series · Sequences and Series
Problem
In a geometric progression the fourth term is 80 and the ninth term is 2560.
(i) Find the first term and the common ratio.
(ii) Hence determine the twelfth term.
(iii) Show that the product of the third and seventh terms equals the square of the fifth term.