Multiplication Of Whole Numbers & Factors Worksheet With Answers - Professor Weissman'S Algebra Classroom Page 2
ADVERTISEMENT
1
2
3
4
5
6
7
8
9
10
11
12Page 2
Multiplication of Whole Numbers & Factors
How Are Powers Of Ten Used?
How Do I Multiply Numbers With
Zeros At the Ends?
#1
#2
Multiply 365 by 1000. There‟s
Multiply 24 by 10
5
There‟s a shortcut when multiplying numbers which
really no need to set up the
end in zeros.
Simply write 24 and then
problem and multiply by with all
#3 Multiply 1300 by 40000
those zeros.
attach 5 zeros (the expo-
nent is 5).
Just multiply 13 by 4 and then add 6 zeros. That‟s
Just write 365 and attach those
the total amount of zeros.
3 zeros that you see in 1000.
24 00000 or 2,400,000
365 000 or 365,000 is the an-
13(4)=52
swer.
52 000000= 52,000,000
How Do I Estimate the Product When I Multiply?
What Properties
To estimate a product, round each number to the first digit. The numbers
Does Multiplication Have?
will have zeros at the end. Multiply these numbers. The result is an esti-
mate of what the actual product should be.
If you recall, Multiplication is repeated addition.
Example: Multiply 7,345 by 497
Multiplication like addition is both Commutative
and Associative.
Round the numbers: 7,000 ( 500)
Commutative: 7•8=8•7
Multiply: 3,500,000
Associative: 3•(4•5)=3•(4•5)
Actual Product: 7,345(497) = 3,650,465
Estimating tells you whether or not your answer is “in the ballpark.”
Addition has an Identity, it‟s zero. Multiplication has
an Identity. It‟s One. If you multiply any number by 1
you don‟t change it‟s value.
What Are Factors Of A Number?
Identity (One): 8∙•1=8
The factors of a number are those numbers that divide ex-
What Are Primes And
actly into the number . You might say that the factors go
Composites?
into the number „evenly‟ with „no remainder.‟
Example #1 What are the
Example #2 What are the fac-
To determine if a number is prime
factors of 12? What 2 num-
tors of 20? What 2 numbers
or composite, follow these steps:
bers multiply to 12. Start
multiply to 20? Start with 1.
with 1
Find all factors of the number.
1.
1(20) = 20
A number is prime If the number
1(12) = 12
2.
2(10) = 20
has only two factors, 1 and itself
2(6) = 12
4(5) = 20
A number is composite if the
3.
3(4) = 12
number has more than 2 fac-
The factors of 20 are:
tors.
The factors of 12 are:
1,2,4,5,10,20
1,2,3,4,6,12
Here are some of the first the
Example #3
Example #4
counting numbers broken into
Find the factors of 5.
Find the factors of 13
Primes (P) and Composites (C)
P= {2,3,5,7,11,13,17,19, … }
1(5) = 5
1(13) = 13
C= {4,6,8,9,10,12,14,15,16, …}
The only factors of 5 are:
The only factors of 13 are:
1 and 5
1 and 13
ADVERTISEMENT
0 votes
Related Articles
Related forms
Related Categories
Parent category: Education