McGraw Hill My Math Grade 5 Chapter 2 Lesson 1 Answer Key Prime Factorization

All the solutions provided in McGraw Hill Math Grade 5 Answer Key PDF Chapter 2 Lesson 1 Prime Factorization will give you a clear idea of the concepts.

McGraw-Hill My Math Grade 5 Answer Key Chapter 2 Lesson 1 Prime Factorization

Talk Math
What are the first ten prime numbers?

Guided Practice

Question 1.
Find the prime factorization of 16.

The prime factorization of 16 is
____ × ____ × ____ × ____
Answer:
2 × 2 × 2 × 2

Explanation:

Independent Practice

Find the prime factorization of each number.

Question 2.
63 = ___
Answer:
3 × 3 × 7 = 3² × 7

Explanation:

Question 3.
18 = ____
Answer:
2 × 3 × 3

Explanation:

Question 4.
40 = ___
Answer:
2 × 2 × 2 × 5

Explanation:

Question 5.
75 = ____
Answer:
3 × 5 × 5

Explanation:

Question 6.
27 = ___
Answer:
3 × 3 × 3

Explanation:

Question 7.
32 = ____
Answer:
2 × 2 × 2 × 2

Explanation:

Question 8.
49 = ____
Answer:
7 × 7

Explanation:

Question 9.
44 = ____
Answer:
11 × 4
11 × 2 × 2

Explanation:

Mathematical PRACTICE 2 Understand Symbols Find the missing number.

Question 10.
104 = 2 × 2 × × 13
= ___
Answer:
x = 2

Explanation:
Let us solve the expression to find the missing number
104 = 2 × 2 × x × 13
104 = 4 × x × 13
104 = 52x
x = 104 ÷ 52
x = 2

Question 11.
55 = × 11
= ___
Answer:
x = 5

Explanation:
Let us solve the expression to find the missing number
55 = x × 11
x = 55 ÷ 11
x = 5

Question 12.
77 = 7 ×
= ___
Answer:
x = 11

Explanation:
Let us solve the expression to find the missing number
77 = 7 × x
x = 77 ÷ 7
x = 11

Problem Solving

Use the table for Exercises 13—16 that shows the average weights of popular dog breeds.

Question 13.
Complete the table.
Answer:

Question 14.
Which weight(s) have a prime factorization of exactly three factors?
Answer:
The weights of cocker spaniel, Golden Retriever, and Siberian Husky.

Question 15.
Which weight(s) have a prime factorization with factors that are all the same number?
Answer:
Beagle

Explanation:
The weight of Beagle has factors that are all the same number.
Beagle 5 × 5

Question 16.
Which breed(s) have weights that are prime numbers?

Answer:
Labrador Retriever.

Explanation:
Labrador Retriever have weights that are prime numbers.

Hot Problems

Question 17.
Mathematical PRACTICE Identify Structure Find the prime factorization of 2,800.
Answer:
The prime factorization of 2,800 is 2⁴ × 5² × 7¹

Explanation:
The prime factorization is 2⁴ × 5² × 7¹

Question 18.
? Building on the Essential Question How do factor trees help you find the prime factorization of a number?
Answer:
First write the given number at the top of the factor tree and and draw two branches.
write the pair of branches with a pair of factor of the number above
Continue this step until each branch ends with a prime number.
Write the solution in a separate line.

McGraw Hill My Math Grade 5 Chapter 2 Lesson 1 My Homework Answer Key

Practice

Find the prime factorization of each number.

Question 1.
50 = ____
Answer:
2 × 5 × 5

Explanation:
The prime factorization of the given number is 2 × 5 × 5.

Question 2.
81 = ___
Answer:
3 × 3 × 3 × 3

Explanation:
The prime factorization of the given number is 3 × 3 × 3 × 3

Question 3.
65 = ___
Answer:
5 × 13

Explanation:
The prime factorization of the given number is 5 × 13.

Question 4.
28 = ___
Answer:
2 × 2 × 7

Explanation:
The prime factorization of the given number is 2 × 2 × 7.

Problem Solving

Question 5.
Britney scored an 85 on her last math test. Write the prime factorization of 85.
Answer:
5 × 17

Explanation:
The prime factorization of 85 is 5 × 17.

Question 6.
Priscilla has 56 stickers in her collection. Write the prime factorization of 56.
Answer:
2 × 2 × 2 × 7

Explanation:
Given 56
we need to find the prime factorization.
Factor of 56
56 = 1 × 56, 2 × 28,  4× 14, 7 × 8
56 = 2 × 2 × 2 × 7

Question 7.
Mathematical PRACTICE 3 Find the Error Lainey wrote the prime factorization of 60 as 2 × 5 × 6. Is she correct? If not, what is the prime factorization of 60? Explain.
Answer:
She is not correct because 6 is not a prime number.
2 × 2 × 5 × 3

Explanation:
She is not correct because 6 is not a prime. It is a composite number. The answer for the prime factorization is  2 × 2 × 5 × 3.

Vocabulary Check

Fill in each blank with the correct term or number to complete the sentence.

Question 8.
___ numbers can be written as a product of factors. This is called the prime factorization of a number.
Answer:
Composite number.

Explanation:
Composite numbers can be written as a product of factors. This is called the prime factorization of a number.

Test Practice

Question 9.
Josiah had a pot belly pig as a pet that weighed 46 pounds. What is the prime factorization of 46?

A. 2 × 23
B. 2 × 2 × 11
C. 2 × 2 × 13
D. 3 × 23
Answer:
46 = 2 × 23

Explanation:
Josiah had a pot belly pig as a pet that weighed 46 pounds
Factors of 46 are 1, 2, 23 and 46
Prime factors = 2 and 23
The prime factorization of 46 is 46 = 2 × 23