MathDB
Similar Geometric Sequences

Source: 2012 AIME II Problem 2

March 29, 2012
ratioAMC

Problem Statement

Two geometric sequences a1,a2,a3, a_1,a_2,a_3,\ldots and b1,b2,b3b_1,b_2,b_3\ldots have the same common ratio, with a1=27a_1=27,b1=99b_1=99, and a15=b11a_{15}=b_{11}. Find a9.a_9.