Final answer:
A ratio is like a fraction as both compare two quantities, but part-to-part ratios differ as they do not reference a whole entity. Fractions follow specific rules for arithmetic operations, while ratios can form proportions when equivalent and can represent unit rates or scales.
Step-by-step explanation:
A part to ratio is similar to a fraction because both represent a relationship between two quantities. A ratio can be written in various forms such as with a colon (2:3), in words ('2 to 3'), or as a fraction (2/3). Like a fraction, ratios compare parts to each other or to a whole. However, a part-to-part ratio, which compares two parts to each other, is not a fraction because it doesn't reference a specific whole. A fraction, on the other hand, typically represents a part of one whole entity.
When working with fractions, understanding the rules for adding, subtracting, multiplying, and dividing is crucial. To add or subtract fractions, you need a common denominator, and you only add the numerators. To multiply fractions, you multiply the numerators and denominators respectively. Division of fractions involves multiplying by the reciprocal of the fraction you're dividing by. A proportion is an equation stating that two ratios, or fractions, are equivalent (1/2 = 3/6). A unit rate is a ratio where one of the quantities is 1 (55 miles/1 hour), and a unit scale compares the dimensions of an actual object to a scale representation (1/2 inch = 100 feet).