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Newsletter 2009
Volume 1, Issue 2
Math 6-Unit 2: Factors &
Multiples
Dear Parents,
Below you will find information regarding Unit 2: Factors and Multiples. Look for additional newsletters for
future units.
Students will be able to:
●
Calculate multiples and factors of given numbers
●
Identify prime and composite numbers
●
Decompose numbers into their prime factorizations
using exponents
●
Determine the least common multiple (LCM) and the
greatest common factor (GCF) for a set of numbers.
Vocabulary
Multiple: The product of a given number and a whole number
Factor: A whole number that divides evenly into another whole number, or a number which is
multiplied by another number to get a product
Least Common Multiple (LCM): The smallest number that is a multiple of two or more given
numbers
Greatest Common Factor (GCF): The largest common factor of two or more given numbers
Prime: A number greater than 1 whose only factors are itself and the 1 (Remember: 1 is neither
prime nor composite)
Composite: A number greater than 1 which has more than 2 factors
Exponents: The number which indicates how many times the base is used as a factor
Prime Factorization: A number written as the product of its prime factors
For more definitions, check
http://intermath.coe.uga.edu/
Holt Mathematics Course 1 by Holt
 Chapter 4: Lessons 1, 2, & 3
 Chapter 5: Lesson 1
Online:
 http://go.hrw.com/gopages/index.html -Holt
Site
 http://mathforum.org/dr.math/faq/faq.divisibili
ty.html
 www.amblesideprimary.com/ambleweb/menta
lmaths/gameshow.html
 www.321know.com/fra63ax2.htm
Ways Parents Can Help
Here are some activities you and your student can do together:
 Items that are used together like hot dogs and buns or paper cups and paper
plates, are often sold in different size packages. Look for examples of these in
stores. Discuss the smallest number of packages of each item that you must buy
so that every hot dog has a bun or every plate has a cup. Ask, “How many hot
dogs with buns would we have to buy to not have any leftovers?” or “How many
place settings (cup and plate) will we have to purchase so that there are an even
number of place settings?”
 Look at the numbers on car license plates or house numbers. Discuss whether the
number is prime or composite and explain how you can tell. If it is composite,
find its prime factorization. You can also use your divisibility rules to tell
whether the numbers are divisible by 2, 3, 4, 5, 6, 8, 9, & 10!
Practice Problems
1. You have 32 apples, 18 pears and 16 bananas to place in gift baskets.
How many gift baskets can you create if you have an equal number of each
fruit in each basket?
2. What is the prime factorization of 180?
3. A CCT bus arrives at a terminal every 15 minutes. A shuttle bus to the
mall arrives at the terminal every 18 minutes. If both buses just arrived to
the terminal, how many more minutes would pass until both buses were at
the terminal at the same time again?
Answers
1. 2 baskets.
Find the greatest common factor (GCF) of 32, 18 and 16
32: 1, 2, 4, 8, 16, 32
18: 1, 2, 3, 6, 9, 18
16: 1, 2, 4, 8, 16
2. 2² x 3² x 5
3. 90 minutes – Find the least common multiple (LCM) for 15 and 18
15: 15, 30, 45, 60, 75, 90
18: 18, 36, 54, 72, 90