Paul used 34 cup of butter in the batch of brownies he made. he ate 16 of the batch of brownies. what fraction of a cup of butter did he consume when he ate the brownies? make math drawings to you solve this problem. explain in detail how your drawings you solve the problem.

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?