Factors
Downloads to help students study:
|
Helpful Links
|
Standards:
4.OA.4 Find all factor pairs for a whole number in the range 1–100. Recognize that a whole number is a multiple of
each of its factors. Determine whether a given whole number in the range 1–100 is a multiple of a given one-digit
number. Determine whether a given whole number in the range 1–100 is prime or composite.
Prime and composite numbers:
Multiples:
Multiples can be thought of as the result of skip counting by each of the factors. When skip counting, students should be able to identify the number of factors counted e.g., 5, 10, 15, 20 (there are 4 fives in 20).
Example:
Factors of 24: 1, 2, 3, 4, 6, 8,12, 24
Multiples of 24: 24, 48, 62
4.NBT.5 Multiply a whole number of up to four digits by a one-digit whole number, and multiply two two-digit numbers, using strategies based on place value and the properties of operations. Illustrate and explain the calculation by using equations, rectangular arrays, and/or area models.
4.OA.4 Find all factor pairs for a whole number in the range 1–100. Recognize that a whole number is a multiple of
each of its factors. Determine whether a given whole number in the range 1–100 is a multiple of a given one-digit
number. Determine whether a given whole number in the range 1–100 is prime or composite.
Prime and composite numbers:
- Prime numbers have exactly two factors, the number one and their own number. For example, the number 17 has the factors of 1 and 17.
- Composite numbers have more than two factors. For example, 8 has the factors 1, 2, 4, and 8.
- A common misconception is that the number 1 is prime, when in fact; it is neither prime nor composite.
- Another common misconception is that all prime numbers are odd numbers. This is not true, since the number 2 has only 2 factors, 1 and 2, and is also an even number.
- Students should understand the process of finding factor pairs so they can do this for any number 1 -100,
Multiples:
Multiples can be thought of as the result of skip counting by each of the factors. When skip counting, students should be able to identify the number of factors counted e.g., 5, 10, 15, 20 (there are 4 fives in 20).
Example:
Factors of 24: 1, 2, 3, 4, 6, 8,12, 24
Multiples of 24: 24, 48, 62
4.NBT.5 Multiply a whole number of up to four digits by a one-digit whole number, and multiply two two-digit numbers, using strategies based on place value and the properties of operations. Illustrate and explain the calculation by using equations, rectangular arrays, and/or area models.