Praxis Core Academic Skills for Educators: Mathematics (5733)Algebra and FunctionsEasy
A baker uses a recipe that calls for 2.5 cups of flour for every 1.5 cups of sugar. If the baker wants to make a larger batch using 7.5 cups of flour, how many cups of sugar will be needed?
- A4.5 cups
- B5.0 cups
- C6.5 cups
- D3.5 cups
Show answer & explanationAnswer & explanation
Correct answer: A. 4.5 cups
This problem involves setting up and solving a proportion. The ratio of flour to sugar is constant. By setting up the proportion 2.5/1.5 = 7.5/x, we can solve for x, which represents the unknown amount of sugar.
Why the other options are wrong
- B. Incorrect. This could be a result of adding instead of multiplying or a calculation error.
- C. Incorrect. This value is too high and likely comes from an incorrect operation or faulty proportion.
- D. Incorrect. This might result from an arithmetic error or incorrect proportion setup.
Proportional Relationships
A proportional relationship exists when two quantities vary in such a way that one is a constant multiple of the other, meaning their ratio is constant.
- Can be expressed as a/b = c/d.
- Involves direct variation.
- Graphs as a straight line through the origin.
Memory trick: Ratio balance, cross-multiply for an unknown prize.