Spreadsheet Help with Cost Splitting

[Keiran Levi]

 Hi

I'm trying to create a spreadsheet which should be simple enough but I'm having some trouble,
So basically I just want the spreadsheet to tell me how much each party should be contributing towards total expenses based on their incomes. They should only ever have a 50/50 split if their incomes are equal. Otherwise, I want the split to be in proportion to their total income.

[#2]

For the amount he pays:

= C15*F7/(F7+F12)

For the amount she pays:

= C15*F12/(F7+F12)

[#3]

Perfect

Thank you so much!