2.5 Prime Factorization and the Least Common Multiple
Breaking a composite number down to primes with a factor tree or ladder, then assembling those primes into the least common multiple of two numbers.
Prealgebra 2e, 2.5 Prime Factorization and the Least Common Multiple
114 exercises
2.5 Exercise 1
Before you get started, take this readiness quiz.
Is divisible by
If you missed this problem, review the reference.
2.5 Exercise 2
Is prime or composite?
If you missed this problem, review the reference.
2.5 Exercise 3
Write in exponential notation.
If you missed this problem, review the reference.
2.5 Exercise 5
Find the prime factorization using the factor tree method:
2.5 Exercise 6
Find the prime factorization using the factor tree method:
2.5 Exercise 8
Find the prime factorization using the factor tree method:
2.5 Exercise 9
Find the prime factorization using the factor tree method:
2.5 Exercise 11
Find the prime factorization using the ladder method:
2.5 Exercise 12
Find the prime factorization using the ladder method:
2.5 Exercise 14
Find the prime factorization using the ladder method.
2.5 Exercise 15
Find the prime factorization using the ladder method.
2.5 Exercise 16
Find the LCM of and by listing multiples.
2.5 Exercise 17
Find the least common multiple (LCM) of the given numbers:
2.5 Exercise 18
Find the least common multiple (LCM) of the given numbers:
2.5 Exercise 20
Find the LCM using the prime factors method.
2.5 Exercise 21
Find the LCM using the prime factors method.
2.5 Exercise 23
Find the LCM using the prime factors method:
2.5 Exercise 24
Find the LCM using the prime factors method:
2.5 Exercise 25
Find the prime factorization of each number using the factor tree method.
2.5 Exercise 27
Find the prime factorization of each number using the factor tree method.
2.5 Exercise 29
Find the prime factorization of each number using the factor tree method.
2.5 Exercise 31
Find the prime factorization of each number using the factor tree method.
2.5 Exercise 33
Find the prime factorization of each number using the factor tree method.
2.5 Exercise 35
Find the prime factorization of each number using the ladder method.
2.5 Exercise 37
Find the prime factorization of each number using the ladder method.
2.5 Exercise 39
Find the prime factorization of each number using the ladder method.
2.5 Exercise 41
Find the prime factorization of each number using the ladder method.
2.5 Exercise 43
Find the prime factorization of each number using the ladder method.
2.5 Exercise 45
Find the prime factorization of each number using any method.
2.5 Exercise 47
Find the prime factorization of each number using any method.
2.5 Exercise 49
Find the prime factorization of each number using any method.
2.5 Exercise 51
Find the prime factorization of each number using any method.
2.5 Exercise 53
Find the least common multiple (LCM) by listing multiples.
2.5 Exercise 55
Find the least common multiple (LCM) by listing multiples.
2.5 Exercise 57
Find the least common multiple (LCM) by listing multiples.
2.5 Exercise 59
Find the least common multiple (LCM) by listing multiples.
2.5 Exercise 61
Find the least common multiple (LCM) by using the prime factors method.
2.5 Exercise 63
Find the least common multiple (LCM) by using the prime factors method.
2.5 Exercise 65
Find the least common multiple (LCM) by using the prime factors method.
2.5 Exercise 67
Find the least common multiple (LCM) using any method.
2.5 Exercise 69
Find the least common multiple (LCM) using any method.
2.5 Exercise 71
Grocery shopping Hot dogs are sold in packages of ten, but hot dog buns come in packs of eight. What is the smallest number of hot dogs and buns that can be purchased if you want to have the same number of hot dogs and buns? (Hint: it is the LCM!)
2.5 Exercise 75
Translate from algebra to English.
2.5 Exercise 77
Translate from algebra to English.
2.5 Exercise 79
Translate from algebra to English.
2.5 Exercise 81
Translate from algebra to English.
2.5 Exercise 83
Determine if each is an expression or equation.
2.5 Exercise 85
Determine if each is an expression or equation.
2.5 Exercise 87
Write in exponential form.
2.5 Exercise 89
Write in exponential form.
2.5 Exercise 91
Write in expanded form.
2.5 Exercise 93
Write in expanded form.
2.5 Exercise 95
Simplify each expression.
2.5 Exercise 97
Simplify each expression.
2.5 Exercise 99
Simplify.
2.5 Exercise 101
Simplify.
2.5 Exercise 103
Simplify.
2.5 Exercise 105
Simplify.
2.5 Exercise 107
Evaluate the following expressions.
2.5 Exercise 109
Evaluate the following expressions.
2.5 Exercise 111
Identify the terms in each expression.
2.5 Exercise 113
Identify the coefficient of each term.
2.5 Exercise 115
Identify the like terms.
2.5 Exercise 117
Simplify the following expressions by combining like terms.
2.5 Exercise 119
Simplify the following expressions by combining like terms.
2.5 Exercise 121
Simplify the following expressions by combining like terms.
2.5 Exercise 123
Simplify the following expressions by combining like terms.
2.5 Exercise 125
Translate the following phrases into algebraic expressions.
the difference of and
2.5 Exercise 127
Translate the following phrases into algebraic expressions.
the product of and
2.5 Exercise 129
Translate the following phrases into algebraic expressions.
times the sum of and
2.5 Exercise 131
Translate the following phrases into algebraic expressions.
Jack bought a sandwich and a coffee. The cost of the sandwich was more than the cost of the coffee. Call the cost of the coffee Write an expression for the cost of the sandwich.
2.5 Exercise 133
Determine whether each number is a solution to the equation.
- ⓐ
- ⓑ
2.5 Exercise 135
Determine whether each number is a solution to the equation.
- ⓐ
- ⓑ
2.5 Exercise 137
Determine whether each number is a solution to the equation.
- ⓐ
- ⓑ
2.5 Exercise 141
Solve each equation using the subtraction property of equality.
2.5 Exercise 143
Solve each equation using the subtraction property of equality.
2.5 Exercise 145
Solve each equation using the addition property of equality.
2.5 Exercise 147
Solve each equation using the addition property of equality.
2.5 Exercise 149
Translate each English sentence into an algebraic equation.
The sum of and is equal to
2.5 Exercise 151
Translate each English sentence into an algebraic equation.
The product of and is equal to
2.5 Exercise 153
Translate each English sentence into an algebraic equation.
Twice the difference of and gives
2.5 Exercise 155
Translate each English sentence into an algebraic equation and then solve it.
Eight more than is equal to
2.5 Exercise 157
Translate each English sentence into an algebraic equation and then solve it.
The difference of and is
2.5 Exercise 159
Solve each equation.
2.5 Exercise 161
Solve each equation.
2.5 Exercise 163
Solve each equation.
2.5 Exercise 165
Solve each equation.
2.5 Exercise 167
List all the multiples less than for each of the following.
2.5 Exercise 169
List all the multiples less than for each of the following.
2.5 Exercise 171
Using the divisibility tests, determine whether each number is divisible by
2.5 Exercise 173
Using the divisibility tests, determine whether each number is divisible by
2.5 Exercise 175
Find all the factors of each number.
2.5 Exercise 177
Find all the factors of each number.
2.5 Exercise 179
Identify each number as prime or composite.
2.5 Exercise 181
Identify each number as prime or composite.
2.5 Exercise 183
Find the prime factorization of each number.
2.5 Exercise 185
Find the prime factorization of each number.
2.5 Exercise 187
Find the least common multiple of each pair of numbers.
2.5 Exercise 189
Find the least common multiple of each pair of numbers.
2.5 Exercise 191
Describe how you have used two topics from The Language of Algebra chapter in your life outside of your math class during the past month.
2.5 Exercise 193
Translate from an algebraic equation to English phrases.
2.5 Exercise 195
Identify each as an expression or equation.
2.5 Exercise 197
Identify each as an expression or equation.
- ⓐ Write in exponential form.
- ⓑ Write in expanded form and then simplify.
2.5 Exercise 199
Simplify, using the order of operations.
2.5 Exercise 201
Simplify, using the order of operations.
2.5 Exercise 203
Simplify, using the order of operations.
2.5 Exercise 205
Evaluate each expression.
2.5 Exercise 207
Evaluate each expression.
2.5 Exercise 209
Translate each phrase into an algebraic expression.
more than
2.5 Exercise 211
Translate each phrase into an algebraic expression.
three times the difference of
2.5 Exercise 213
Solve each equation.
2.5 Exercise 215
Translate each English sentence into an algebraic equation and then solve it.
less than is
2.5 Exercise 217
Translate each English sentence into an algebraic equation and then solve it.
List all the multiples of that are less than
2.5 Exercise 219
Translate each English sentence into an algebraic equation and then solve it.
Find the prime factorization of
Adapted from Prealgebra 2e © 2020 Rice University. Licensed under CC BY 4.0. Source: Prealgebra 2e. Imported at revision 77a933c.