Math Skill: Factoring

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Factoring

Factoring a number is when we find all the whole numbers that can be divided evenly into that number.

For example,

15 ÷ 3 = 5		3 and 5 are factors of 15
15 ÷ 6 = 2.5		6 is NOT a factor of 15 because 6 does not divide evenly into 15

Here are some divisibility rules that should help:
Divisibility by 2: If the number ends in 0,2,4,6, or 8, it is divisible by 2.
Divisibility by 3: If the sum of the digits is divisible by 3, the number is divisible by 3.  
   Example: 27 is divisible by 3 because 2 + 7 = 9, which is divisible by 3.
Divisibility by 4: If the last two digits are divisible by 4.
Divisibility by 5: If the number ends in 0 or 5, it is divisible by 5.
Divisibility by 6: If the number is divisible by 2 and 3.
Divisibility by 9: If the sum of the digits is divisible by 9.
Divisibility by 10: If the last digit is 0.

Examples:

Find all the factors of each number in increasing order. Example: The factors of 10 are "1 2 5 10".

12
25
28
31

Complexity=8

Find all the factors of each number in increasing order. Example: The factors of 10 are "1 2 5 10".
Make sure you add a space between each number.

1. 4

2. 8

Complexity=12

Find all the factors of each number in increasing order. Example: The factors of 10 are "1 2 5 10".
Make sure you add a space between each number.

1. 4

2. 8

Complexity=20

Find all the factors of each number in increasing order. Example: The factors of 10 are "1 2 5 10".
Make sure you add a space between each number.

1. 14

2. 10

Complexity=30

Find all the factors of each number in increasing order. Example: The factors of 10 are "1 2 5 10".
Make sure you add a space between each number.

1. 27

2. 17

Complexity=40

Find all the factors of each number in increasing order. Example: The factors of 10 are "1 2 5 10".
Make sure you add a space between each number.

1. 21

2. 22

Complexity=50

Find all the factors of each number in increasing order. Example: The factors of 10 are "1 2 5 10".
Make sure you add a space between each number.

1. 36

2. 41

Complexity=80

Find all the factors of each number in increasing order. Example: The factors of 10 are "1 2 5 10".
Make sure you add a space between each number.

1. 42

2. 52

Complexity=150

Find all the factors of each number in increasing order. Example: The factors of 10 are "1 2 5 10".
Make sure you add a space between each number.

1. 90

2. 109

Answers

Complexity=8

Find all the factors of each number in increasing order. Example: The factors of 10 are "1 2 5 10".
Make sure you add a space between each number.

#	Problem	Correct Answer	Your Answer
1	4

#	Problem	Correct Answer	Your Answer
2	8

Complexity=12

Find all the factors of each number in increasing order. Example: The factors of 10 are "1 2 5 10".
Make sure you add a space between each number.

#	Problem	Correct Answer	Your Answer
1	4

#	Problem	Correct Answer	Your Answer
2	8

Complexity=20

Find all the factors of each number in increasing order. Example: The factors of 10 are "1 2 5 10".
Make sure you add a space between each number.

#	Problem	Correct Answer	Your Answer
1	14

#	Problem	Correct Answer	Your Answer
2	10

Complexity=30

Find all the factors of each number in increasing order. Example: The factors of 10 are "1 2 5 10".
Make sure you add a space between each number.

#	Problem	Correct Answer	Your Answer
1	27

#	Problem	Correct Answer	Your Answer
2	17

Complexity=40

Find all the factors of each number in increasing order. Example: The factors of 10 are "1 2 5 10".
Make sure you add a space between each number.

#	Problem	Correct Answer	Your Answer
1	21

#	Problem	Correct Answer	Your Answer
2	22

Complexity=50

Find all the factors of each number in increasing order. Example: The factors of 10 are "1 2 5 10".
Make sure you add a space between each number.

#	Problem	Correct Answer	Your Answer
1	36

#	Problem	Correct Answer	Your Answer
2	41

Complexity=80

Find all the factors of each number in increasing order. Example: The factors of 10 are "1 2 5 10".
Make sure you add a space between each number.

#	Problem	Correct Answer	Your Answer
1	42

#	Problem	Correct Answer	Your Answer
2	52

Complexity=150

Find all the factors of each number in increasing order. Example: The factors of 10 are "1 2 5 10".
Make sure you add a space between each number.

#	Problem	Correct Answer	Your Answer
1	90

#	Problem	Correct Answer	Your Answer
2	109

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