NUMBER SENSE

Percentages

A way to represent part-to-whole relationships, where the percent is the part out of 100.

Example.

One half: 50%=12=0.5050%=21​=0.50

Numerator

the top term of a fraction

Example.

In 110101​ the numerator is 1

Factors

Values that are multiplied to get another number.

Example.

Some factors of 12 are 3 and 4 because 3×4=123×4=12

Double Number Line Diagram

Consists of two parallel number lines, each representing a different unit

Used to visualize and compare ratios

Example.

Reducing Fractions

dividing the numerator and denominator by any common factors to put the fraction in lowest terms

Example.

Fraction Composition

Adding fractions to come up with a larger one

Example.

¼ + ¼ + ¼ = ¾

Denominator

the bottom term of a fraction

EXAMPLE:

Fraction Decomposition

Breaking down a fraction into smaller fractions that total to the original

Example.

2/3 = 1/3 + 1/3

Least Common Multiple (LCM)

the smallest number that is a multiple of two or more numbers; the smallest number two or more numbers will divide into evenly

Example.

For 12 and 15, LCM = 60

Multiples of 12: 12, 24, 36, 48, 60

Multiples of 15: 15, 30, 45, 60

Fractions

usually represent partial numbers

Example.

One half: 50%= 1/2 =0.50

Factor Tree

A visual process to find the factors of a number

Composite Numbers

natural numbers that are divisible by numbers other than one and themselves

Example.

6 is divisible by 2 and 3

Decimal Fractions

fractions with a denominator of 10

Example.

Greatest Common Factor (GCF) / Greatest Common Divisor (GCD)

the greatest factor that is common to two or more numbers; the largest number that will divide evenly into two or more numbers

Example.

For 12 and 15, GCF = 3

Factors of 12: 1, 2, 3, 4, 6, 12

Factors of 15: 1, 3, 5, 15

Order of Operations

PEMDAS: the set order in which multi-step equations must be solved: Parenthesis, Exponents, Multiplication and Division (left to right), Addition and Subtraction (left to right)

Relatively Prime

two numbers are relatively prime if they share no common factors

Example.

34 and 15

Prime Factorization

the process of writing a number in terms of its prime factors

Example.

12=2×2×312=2×2×3

Decimal

Numbers less than 1 displayed using place values and the powers of ten

Example.

0.024

Ratio

A comparison that shows the relative size of two or more values.

Example.

The ratio of boys to girls is: 4 to 5; 4:5; 4/5; 0.8.

Prime Numbers

natural numbers greater than 1 that have no numbers that will divide into them without a remainder

Example.

2, 3, 5, 7....

Real Numbers

numbers that have a specific value

Example.

-2, 3, 1/2, 3.2, √2

Prime Factor

a prime number or term that can be multiplied by another to get a number.

Example.

2×6=122×6=12, 2 is a prime factor