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6: Ratio, Proportion, and Measurement

  • Page ID
    47255
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    • 6.1: Ratio and Proportion
      Examples and applications of ratios are limitless: speed is a ratio that compares changes in distance with respect to time, acceleration is a ratio that compares changes in speed with respect to time, and percentages compare the part with the whole. We’ve already studied one classic ratio, the ratio of the circumference of a circle to its diameter, which gives us the definition of π.
    • 6.2: Introduction to Ratios and Rates
      We use ratios to compare two numeric quantities or quantities with the same units.
    • 6.3: Introduction to Proportion
      In this section, we equate ratio and rates in a construct called a proportion.
    • 6.4: Unit Conversion - American System
      In this section we will develop a technique for converting units used in the American system. We begin with a discussion of common measurements of length in the United States.
    • 6.5: Unit Conversion- Metric System
      The metric system of units is the standard system of units preferred by scientists. It is based on the base ten number system and its decimal format is more friendly to users of this system. There is a common set of prefixes adopted by the metric system to indicate a power of ten to apply to the base unit.
    • 6.6: American Units to Metric Units and Vice-Versa
      We often need to convert from the American system of units to the metric system of units or vice-versa (imagine traveling to a European country using the metric system). That will be our focus in this section.
    • 6.7: Use a Problem Solving Strategy (Part 1)
      In earlier chapters, you translated word phrases into algebraic expressions and word sentences into algebraic equations and solved some word problems that applied math to everyday situations. You had to restate the situation in one sentence, assign a variable, and then write an equation to solve. This method works as long as the situation is familiar to you and the math is not too complicated. Now we'll develop a strategy you can use to solve any word problem.
    • 6.8: Use a Problem Solving Strategy (Part 2)
      In number problems, you are given some clues about one or more numbers, and you use these clues to build an equation. Number problems don't usually arise on an everyday basis, but they provide a good introduction to practicing the Problem Solving Strategy. Some number word problems ask you to find two or more numbers. Be sure to read the problem carefully to discover how all the numbers relate to each other.
    • 6.9: Solve a Formula for a Specific Variable
      For an object moving in at a uniform (constant) rate, the distance traveled, the elapsed time, and the rate are related by the formula d = rt where d = distance, r = rate, and t = time. To solve a formula for a specific variable means to get that variable by itself with a coefficient of 1 on one side of the equation and all the other variables and constants on the other side. The result is another formula, made up only of variables.
    • 6.E: Math Models and Geometry (Exercises)
    • 6.S: Math Models and Geometry (Summary)


    This page titled 6: Ratio, Proportion, and Measurement is shared under a CC BY-NC-SA license and was authored, remixed, and/or curated by David Arnold.

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