Multiplication Properties
Name the property
5 x (3 x 1) = (5 x 3) x 1
Associative Property of Multiplication
What are all of the partial products for 27 x 5?
A. 35, 10
B. 12, 7
C. 35, 100
C. 35, 100
25 x 5 =
125
Estimate by rounding.
88 x 51
90 x 50 = 4,500
A box of crayons has 64 crayons in it. Every student in the grade has one. box. There are 44 people in the grade. About how many crayons is that total? (Estimate)
60 x 40 = 2,400 crayons
Name the property.
3 x 25 = 25 x 3
Commutative Property of Multiplication
How can you use the distributive property to find 5 x 37?
(5 x 30) + (5 x 7)
415 x 3 =
1,245
Use rounding to estimate:
480 x 7
500 x 7 = 3,500
A restaurant sells an average of 9 hamburgers a day. How many would this mean they sell in a year? (Assume a year is 365 days.)
365 x 9 = 3,285 hamburgers
Is the partial products strategy a property of multiplication?
No, it is a strategy for solving a multiplication problem.
Which expression can be used to find 8 x 45?
A. (8 + 40 + 5)
B. (8 x 40) + (8 x 5)
C. (8 x 40) x (8 x 5)
D. (8 + 40) + (8+ 5)
B. (8 x 40) + (8 x 5)
7,709 x 6 =
46, 254
Estimate using rounding:
$421 x 62 =
$400 x 60 = $24,000
A ticket to an Orioles game cost $149. How much would it be to buy a ticket to 8 games?
$149 x 8 = $1,192
Name the property.
10 x (4 + 3) = (10 x 4) + (10 x 3)
Distributive Property
Name the partial products for 831 x 7.
7 210 5,600
Use standard algorithm to solve this problem.
A store has 7 boxes each filled with 88 plates. How many plates are in all seven boxes?
616 plates
Use rounding to estimate
8 x 7,632
8 x 8,000 = 64,000
Mia has a collection of 2,497 stickers. A toy store has 6 times as many stickers. How many stickers does the store have?
2,497 x 6 =14, 982 stickers
What property says that it doesn't matter what order the factors are multiplied in, that the product will still be the same?
Commutative Property of Multiplication
Use partial products to solve 3,499 x 8.
3,499 x 8 = 27, 992
8x9 = 72
8x90 = 720
8x400 = 3,200
8x3,000 = 24,000
Find 9,850 x 4
39,400
Use rounding to estimate:
450 x 199
500 x 200 = 100,000
The Jessup Family pays $ 2,125 a month in rent. Mr. Jessup estimates that the family spends about $ 24,000 per year on rent. Is his estimate reasonable?
Yes, because $2,125 is about 2,000
$2,000 x 12 = $24,000