Rational Number
Definition: A rational number is a type of number that can be expressed as a fraction, where the top part (called the numerator) is an integer (a whole number), and the bottom part (called the denominator) is also an integer, but it cannot be zero. In simpler terms, if you can write a number as a fraction, it is a rational number.
Usage Instructions: You can use the term "rational number" when discussing mathematics, particularly when talking about different types of numbers. You will often see rational numbers in everyday situations, such as in measurements or when dealing with money.
Example: - The number 1/2 is a rational number because it can be expressed as a fraction (1 is the numerator and 2 is the denominator). - The number 3 is also a rational number because it can be written as 3/1 (3 is the numerator and 1 is the denominator).
Advanced Usage: - Rational numbers can be positive or negative. For example, -4/5 is a rational number. - All integers (like -3, 0, and 5) are also rational numbers because they can be represented as fractions (-3/1, 0/1, and 5/1).
Word Variants: - The adjective form is "rational," which describes something based on reason or logic. For example, "He made a rational decision." - The opposite of a rational number is an "irrational number," which cannot be expressed as a fraction, such as √2 or π (pi).
Different Meaning: - In a non-mathematical context, "rational" can refer to being reasonable or logical. For example, "Her explanation was rational and easy to understand."
Synonyms: - Fractional number - Integer (when referring to whole numbers) - Whole number (for non-fractional rational numbers)
Idioms/Phrasal Verbs: - While there are no direct idioms or phrasal verbs specifically related to "rational number," you might encounter phrases like "keep your numbers straight," which means to be clear and accurate with numerical information.
In summary, a rational number is any number that can be made into a fraction, which includes integers and fractions themselves.