Charlie had $54.50 in savings. He purchased chips and a soda every week on Friday totaling $2.50. If his savings is currently $43.25, how many weeks did he purchase chips and a soda?
Is this an Equation or inequality problem?
Equation
Inequality

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?