Part time job creation

Hi I would like to know more about the hiring part-time employees under Tier 1 Entrepreneurship visa.
I Understand I need to create or 2 full time positions under this visa.
My question is if I have to create part-time positions rather than Full time, can I only create 4 part time with min. working hours 15 hours per week each or can I actually hire more then 4 part time given I need a variety of jobs done And the skill set required are all really different.

For example can I hire one part-time for 10 hours and another one for 20 hours per week which will make up to 1 full time?
Can I also hire more than four full time if I need to hire 3 part time for 10 hours per week which will make up to 1 full time per week?

Thank you for the help!