Bob does not sell any scarves. (If he does, there isn't enough information here to solve the problem.)
Suppose Bob ends the day with 7k hats and 9k scarves, where k is some integer. This is a ratio of 7:9. Bob started the day with 7k+25 hats and 9k scarves. The ratio at the start of the day is
(7k+25)/9k = 4/3
3(7k+25) = 4(9k)
21k+75= 36k
75 = 15k
k = 5.
So Bob has 9k = 9x5 = 45 scarves.
Suppose Jake gets £ 1k and Kim gets £ 3k. Kim gets £ 2k more than Jake, so £ 2k = £ 9.
Lee gets £ 6k = 3x £ 2k = 3x £ 9 = £ 27.
The co-ordinates of X are
x = 2 + (2/5)*(12.5-2) = 6.2
y = 1 + (2/5)*(7.5-1) = 3.6.