Download Chapter 1 Study Guide

Unit 1 Study Guide
Vocabulary Words (Quizzes will include vocabulary words)
Array- a rectangular arrangement that has an equal number of objects in each row and an equal number of
objects in each column. (P. 4)
*An array for the #15 can be shown as 3 x 5. There are 3 rows with 5 objects in each row. The array can also be
made as 5 x 3. There are 5 rows with 3 objects in each row.
Factor pairs- two natural numbers other than zero that are multiplied together to produce another number.
(P. 5) List all the factor pairs of 21
__21_
1 x 21
3x7
Factors- two numbers that when multiplied together equal another number. (P. 5)
The #21 has 4 factors 1, 3, 7, 21
CF (Common Factors)
15 and 30:
Write out all the factors of 15 and 30.
15______
1 x 15
3x5
__30__
1 x 30
2 x 15
3 x 10
5x6
The CF of 15 and 30 are 1,3,5,15
Distinct factors- factors that appear only once in a list. (P. 6)
We said the #30 has 8 distinct factors. Each factor is ONLY used once.
The #9 has 3 distinct factors. 1,3, 9 The #9 is a square number so we only count 3 one time.
___9__
1x9
3x3
Commutative Property of Multiplication states that changing the order of two or more factors does not
change the product. (P. 5)
For any numbers a and b, a x b= b x a
4x7=7x4
Set- a collection of numbers, geometric figures, letters, or other objects that have some characteristic in
common. (P. 26)
Perfect square- a number multiplied by itself forms a square. (P. 8) (5th grade AKA Square numbers)
Example 5 x 5
Multiples- the product of a given whole number and another whole number. (P. 13)
The multiples of the #8 is 8, 16, 24, 32, 40, 48 and so on
8x1 8x2 8x3 8x4 8x5 8x6
Venn diagram- a picture that illustrates the relationships between two or more sets. (P. 26)
Prime and Composite
*0 and 1 are neither prime nor composite.
*2, 3, 5, 7, 11, 13, 17, 19 are prime because they have only two factors. The only way to get to the produce by
multiplying is 1 times the number. (Example: 19: only way to get to it is 1 X 19).
*4 is composite because it has more than 2 factors. You can multiply 1x4 and 2x2. 4 has 3 factors (1, 2, and
4).
Prime- a number that has only 2 factors. (P. 32)
__7__
1x7
The #7 has only 2 factors
1 and 7
Composite- a number that has more than two factors. (P. 32)
__14__
1x14
2x7
The #14 has 4 factors 1,2,7,14
Multiplicative Identity- a number that when multiplied by a second number, the product is the second number.
Example: 1 x 8 = 8
Divisible- one number is divisible by the second number when the second number divides “evenly” into the
first number with no remainder. (P. 14)
Divisibility Rules: (P 36-39)
Numbers
2
3
5
6
9
10
Rule
Digit in the ones column must be a 0, 2, 4, 6, 8
Add the digits together. If the sum is a multiple of 3, the number can be divided by 3.
Digit in the ones column must be a 0 or 5
MUST be divisible by both 2 and 3
Add the digits together. If the sum is a multiple of 9, the number can be divided by 9.
Digit in the ones column must be a 0
*In fourth grade, students learned about divisibility rules of 2, 5, and 10. These rules apply to the digit in the
ONES column.
*In fifth grade, students learned about divisibility rules of 3, 6, and 9. The rules of 3 and 9 are very similar.
Students need to add the sum of the digits together to determine divisibility. To determine the rule of 6, both 2
and 3 must be divisible by the number.