Positive Numbers and the Number Line

Unit 1 – Classifying Numbers

Vocabulary Natural Numbers – The set of counting numbers {1, 2, 3, 4…} Whole Numbers – The set of counting numbers and zero {0, 1, 2, 3…} Integers – The set of whole numbers and their opposites {…-2, -1, 0, 1, 2…} Rational Numbers – The set of integers and all fractions, terminating decimals and repeating decimals Irrational Numbers – The set of numbers that can not be expressed as a fraction. This includes all non-repeating decimals. Real Numbers – The set of numbers that includes all rational and irrational numbers.

Famous Irrational Numbers Pi 𝛑 𝜋 is the circumference of a circle divided by its diameter and is used in circle calculations. The first few digits are: 3.1415926535897 Euler’s Number e e is the base of the Natural Logarithms (which you won’t deal with until HS). The first few digits are: 2.71828182845904523 Golden Ratio 𝛗 φ (symbol is the Greek letter "phi”) is a special number that appears many times in geometry, art & architecture. The first few digits are: 1.618033988749894

Guided Practice Classifying Numbers: For each number, write: real, irrational, rational, integer, whole and/or natural. LIST ALL WORDS THAT APPLY. 7 6.523 12½ -1,436 natural, whole, integer, rational & real rational & real integer, rational & real whole, integer, rational & real

Guided Practice Classifying Numbers: For each number, write: real, irrational, rational, integer, whole and/or natural. LIST ALL WORDS THAT APPLY. -9.432 -6¼ π 124,985 -147 rational & real irrational & real natural, whole, integer, rational & real integer, rational & real