Answer:
Correct answers: Part A: Moe = 2500 + 125n and Meo = 2000 + 150n. Part B: oe: 12 machines; eo: 14 machines. Part C: 20 machines or higher.
PARCC evidence statement(s) tested: HS.D.1-1:
Solve multi-step contextual problems with degree of difficulty appropriate to the course, requiring application of knowledge and skills articulated in 7.RP.A, 7.NS.3, 7.EE, and/or 8.EE.
The evidence statement above references mainly Math Practice 4 in the Common Core:
[MP.4] Model with mathematics. Mathematically proficient students can apply the mathematics they know to solve problems arising in everyday life, society, and the workplace. … By high school, a student might use geometry to solve a design problem or use a function to describe how one quantity of interest depends on another. Mathematically proficient students who can apply what they know are comfortable making assumptions and approximations to simplify a complicated situation, realizing that these may need revision later. They are able to identify important quantities in a practical situation and map their relationships using such tools as diagrams, two-way tables, graphs, flowcharts and formulas. They can analyze those relationships mathematically to draw conclusions. They routinely interpret their mathematical results in the context of the situation and reflect on whether the results make sense, possibly improving the model if it has not served its purpose.
It may also reference other standards of mathematical practice, including MP.1 (make sense of problems and persevere in solving them), MP.2 (reason abstractly and quantitatively), and MP.5 (use appropriate tools strategically).
The question requires students’ prior understanding of the eighth-grade Common Core standard 8.EE.C, found under Expressions and Equations (analyze and solve linear equations and pairs of simultaneous linear equations), which states that they should be able to [EE.C.7] “solve linear equations in one variable” and [EE.C.8] “analyze and solve pairs of simultaneous linear equations.”
Note that the PARCC question referenced here simply uses understanding of these standards from eighth grade, considering this understanding to be securely-held knowledge. The PARCC question in Algebra 1 tests students’ ability to model with mathematics, as referenced in Math Practice 4.
Explanation: