50 points! ASAP!

Can someone answer this, and show their work?
Thank you!

With #! i’ve tried to figure it out but i can’t.

Divide. write in simplest form 41/6 divided by 10

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?