Work. Do Not Solve

question 22

Multiple Choice

work. Do not solve.
-5x + 9y = -12
-4x - 4y = -32
A) Substitution B) Addition
Answer: B
Write the word or phrase that best completes each statement or answers the question.
-Dmitri needs 9 liters of a 69% solution of sulfuric acid for a research project in molecular biology. He has two supplies of sulfuric acid solution: one is an unlimited supply of the 81% solution and
The other an unlimited supply of the 54% solution. How many liters of each solution should Dmitri
Use?

• A) Substitution B) Addition
• Answer: B
• Write the word or phrase that best completes each statement or answers the question.
• -Dmitri needs 9 liters of a 69% solution of sulfuric acid for a research project in molecular biology. He has two supplies of sulfuric acid solution: one is an unlimited supply of the 81% solution and
• The other an unlimited supply of the 54% solution. How many liters of each solution should Dmitri
• Use?
• A) 5.5 L of 81% solution; 3.5 L of 54% solution
• B) 4 L of 81% solution; 5 L of 54% solution
• C) 4.5 L of 81% solution; 4.5 L of 54% solution
• D) 5 L of 81% solution; 4 L of 54% solution

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Definitions:

Saving

The act of setting aside a portion of one’s income for future use, instead of spending it immediately.

Disposable Income

After subtracting income taxes, disposable income is the money remaining for individuals or households to spend or save.

MPC

The marginal propensity to consume, indicating the proportion of an additional unit of income that is spent on consumption.

MPS

Marginal Propensity to Save, which is the portion of additional income that a household saves rather than consumes.