Gr.7 Math: 1.1, 1.2
Chap.1 Factors and Exponents – Lesson #1
P.2-3 Getting Started
Factor: a _whole______ number (not including zero_) that _divides_ into another whole number
with no __remainder_.
Multiple: the _product___ of a ____whole_ number when multiplied by any other whole
number.
Prime Number: a number with only __two_ factors, _one__ and ____itself___.
What are the prime numbers between 1 and 20? _2, 3, 5, 7, 11, 13, 17, 19___
Which prime number is uniquely different from the rest and why? Two because it is even.
Composite Number: a whole number greater than _one that has _____more__ than two factors.
Two whole numbers are neither prime nor composite; they are _zero__ and _one_.
Circle the composite numbers in this list:
45,
23,
36,
39,
27,
21,
31,
15,
11
Sec.1.1 Using Multiples p.4
Miss Wagner is going to have a campfire with all the BCS staff and she wants to bring S’mores.
Based on Mr. Cabrels love of S’mores she wants to bring about 100 without any leftover
marshmellows, chocolate or graham crackers.
A&B
# of Packages
1
2
3
4
5
6
7
8
9
10
# of
12
24
36
48
60
72
84
96
108 120
Marshmellows
(Multiples of
12)
# of Chocolate 8
16
24
32
40
48
56
64
72
80
Bars
(Multiples of
8)
# of Graham
4
8
12
16
20
24
28
32
36
40
Crackers
(Multiples of
4)
Extension *How do we know that Graham Crackers also have a multiple of 96?
C. Circle the multiples that are common to both numbers in the table above.
D. The least common multiple (LCM) of 12, 8 and 4 is ___24____.
11
132
12
144
88
96
44
48
Gr.7 Math: 1.1, 1.2
E. How would you use the LCM to find the number of packages to buy?
You can multiply the LCM to find the number closest to one hundred. This number will have
factors of marshmallows, chocolate and graham crackers. The factors that multiply the LCM to
get to your number closest to one hundred (in our case 96) is the number of packages you will
need of each item.
F. How many packages of Marshmellows, Chocolate and Craham Crackers should Miss Wagner
buy to make it close to 100 S’mores?
Marshmellows: 8 packages
Chocolate: 12 packages
Craham Crackers: 24 packages
Least Common Multiple (LCM): the _least_ whole number that has two or more given
numbers as __factors__.
SUMMARY:
To find the least common multiple of two or more numbers: list the multiples of each number
from least to greatest until you arrive at the first multiple each number has in common.
Try this: Find the LCM of 3, 6, and 7
3, __3, 6, 9, 12, 15, 18, 21, 24, 27, 30, 33, 36, 39, 42
6, _6, 12, 18, 24, 30, 36, 42,_______
7, 7, 14, 21, 28, 35, 42, _____
Question: What is the LCM of 1 and any other number?
Eg. The LCM of 1 and 33 is __33__, because: one is a multiple of any other number
__________________________________________________________________
Assignment: P.3 # 1, 2
P. 6-7 # 8, 9, 10, 11 CE, 12, 16AB, 18
Due: _________________________
Extra Questions (Optional): P. 4 A-E # 1