This equation shows how the number of pies Manny can bake is related to the number of additional cups of sugar he buys. p = 2s + 92

The variable s represents the number of additional cups of sugar Manny buys, and the variable p represents the total number of pies he can bake. How many additional cups of sugar does Manny need in order to bake a total of 100 pies?

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?