30 May 2015
X and Y share in 4:1 i.e. 4/5 & 1/5. 1/5th share of Y will be shares between Y & Z in 4:1. Their new share will be Y = 1/5 x 4/5 = 4/25 Z = 1/5 x 1/5 = 1/25
X's share remains unchanged but will be converted to common base 25 as follows: X = 4/5 x 5/5 = 20/25 New share of X, Y & Z 20/25, 4/25 & 1/25 or 20:4:1