If a, b, c are in geometric progression (GP) and x, y are the arithmetic means between a and b, and b and c respectively, then which of the following is/are true?
1) x = (a + b) / 2 and y = (b + c) / 2
2) x = (a + b) / 2 and y = (a + c) / 2
3) x = (a + c) / 2 and y = (b + c) / 2
4) x = (a + c) / 2 and y = (a + b) / 2