PRAXIS: CORE STUDY GUIDE 2024
Whole Numbers
โ 0 and go on forever: 1, 2, 3 and so on. Each whole number is separated from the
next by a quantity of 1
Partial Numbers
โ Fractions and decimals; not whole numbers
Positive and Negative numbers
โ a negative number is the opposite of a positive number, and vice versa.
Integers
โ All the whole numbers and their opposites. The only integer that doesn't have an
opposite is 0
Absolute Value
โ an integer's positive distance from 0. It's value without a negative sign.
Ex: |4| = 4 or |-4| = 4
Working with integers
โ * Subtracting an integer is the same as adding its opposite, and adding a number is
the same as subtracting its opposite.
*If an even number of negative integers are multiplied or divided, the product is positive.
If an odd number of negative integers are multiplied or divided, the product is negative.
*To add two integers with the same sign, add their absolute values and give the sum of
the sign that both numbers have
* To add two integers with opposite signs, subtract the smaller absolute value from the
greater absolute value and give the difference the sign of the number with the greater
absolute value.
Factor
โ a factor of a whole number is the whole number that can be divided into it a whole
number of times.
Remember: every whole number has itself and 1 for factors. If those are the only two
factors of a number its a prime number.
Prime number
โ a whole number that only has itself and 1 for factors.
Prime factorization
โ a representation of the number as a product of all its prime factors.
greatest common factor vs least common multiple
โ GCF: greatest factor in common (20: 1, 2, 4, 5, 10, 20)
