Geometric Progression

The first, second and seventh terms of an arithmetic progression (all the terms are distinct) are in geometric progression and the sum of these three terms is 93. Then, the fourth term of this geometric progression is

If a, b and c are positive numbers in arithmetic progression and a^(2), b^(2) and c^(2) are in geometric progression, then a^(3), b^(3) and c^(3) are in (A) arithmetic progression. (B) geometric progression. (C) harmonic progression.

Let three positive numbers a, b c are in geometric progression, such that a, b+8 , c are in arithmetic progression and a, b+8, c+64 are in geometric progression. If the arithmetic mean of a, b, c is k, then (3)/(13)k is equal to

Define Geometrical progression.

Who gave principle that man tends to multiply by geometrical progression then food supply?