NEED HELP ASAPCan someone help me!???!

Asocial networking site currently has 400,000 active members, and that figure is predicted to increase by 32% each year. the following expression represents the number of active members on the site after t years.

Each person in an it department of 25 people works on at least one of 3 major projects: system security, program implementation, platform development. 10 people work on system security, 13 work on program implementation, and 12 work on platform development. 4 people work on system security and platform development, 5 people work on program implementation and platform development, and 2 people work on all three projects. how many people work on system security and program implementation?

What is the sum of these mixed numbers 4 2/3+ 3 1/9