Partnership 裡面經常有1:1:1 ,1:1:3....係點計出嚟ga?

計Partnership ge時侯,會出現比數 ~ 1:1:1 ,1:1:3...應該點計ga..?
e.g. ~

A,B and C have been in business sharing profits /losses equally for many years
They decided to share profits in the ratio of A,B and C 1:1:3 from 1 Sep 19.
The followin information has been extracted from their books for Year 19:

Sales 750,000
Cost of goods sold 52% of sales value
Expenses varying on sales basis 15% of sales value
Expenses varying on time basis 16% of sales value
An exceptional expense that was incurred on 3 Apr Year 19 17,500
An exceptional expense that was incurred on 5 Nov Year 19 11,000

The average monthly sales for the 6 months to 30 jun year 19 was 150% times
the average monthly sales for the 6 months to 31 Dec Year 19.

答案係要將750K 分開 1:1:1 & 1:1:3 ~ 550 K & 200K
不過,我唔明白係點樣計到出嚟ar...? 有冇人可以幫幫手..?
Thks !!!