hi SandraN
Thank you for your post, I'd like to extend you a warm welcome to the Community Forum, I hope you find it a valuable resource.
Within MYOB you can create a rule to split based on a percentage. Under Banking>>Manage Rules you can create a rule for these types of transactions. Under the allocate to section you have the option to allocate by either percentage.
When you split transaction using a rule, you can nominate both accounts and different tax code for those transactions. If you were unsure to which account or tax code to use, I recommend speaking to your accountant.
Let me know if you require any further assistance with this. I'm happy to assist you.
If my response has answered your inquiry please click "Accept as Solution" to assist other users find this information.
Cheers.
Cel