Mrs perry shares out 15 biscuites between gemma and zak in the ratio 1: 4 how many biscuites do they get each? gemma: zak

Number of biscuits shared by Mrs Perry = 25
ratio in which the biscuits were shared between Gemma and Zak = 1:4
Let us assume the common ratio = x
then
x + 4x = 15
5x = 15
x = 3
Then
The number of biscuits that Gemma got = 3
The number of biscuits that Zak got = 4x
                                                          = 4 * 3
                                                           = 12
So
Gemma: Zak = 3:12
I hope the procedure is clear enough for you to understand.