Unit 1-14 Multiplication Patterns

1–14
Name
Date
Multiplication Patterns
Finding multiplication patterns can help you multiply quickly and easily.
1.
Write the multiplications for 9 from 2 ⫻ 9 through 9 ⫻ 9.
2.
Compare the tens digit of each product with the multiplier of 9. What do you notice?
3.
Add the digits in each product. What do you notice?
Look at the pattern for multiplying a 1-digit number and 11.
1 ⫻ 11 = 11 2 ⫻ 11 = 22 3 ⫻ 11 = 33
4.
4 ⫻ 11 = 44
5 ⫻ 11 = 55
Use the pattern to predict the products of 7 ⫻ 11 and 9 ⫻ 11.
Now look at the pattern for multiplying 11 by a 2-digit number whose digits have a sum
less than 10.
11 ⫻ 11= 121
12 ⫻ 11 = 132
13 ⫻ 11 = 143
14 ⫻ 11 = 154
5.
Compare the hundreds digit in each product with the tens digit in the multiplier of 11.
What do you notice?
6.
Compare the ones digit in each product with the ones digit in the multiplier of 11. What
do you notice?
7.
Compare the tens digit in each product with the sum of the digits in the multiplier of 11.
What do you notice?
8.
Use the pattern to predict the product: 15 ⫻ 11 =
24 ⫻ 11 =
32 ⫻ 11 =
54 ⫻ 11 =
63 ⫻ 11 =
41 ⫻ 11 =
18 ⫻ 11 =
Copyright © Houghton Mifflin Company. All rights reserved.
10 ⫻ 11 = 110
Name
1–14
Date
Multiplication Patterns
Finding multiplication patterns can help you multiply quickly and easily.
1.
Write the multiplications for 9 from 2 ⫻ 9 through 9 ⫻ 9.
2 ⫻ 9 = 18; 3 ⫻ 9 = 27; 4 ⫻ 9 = 36; 5 ⫻ 9 = 45;
6 ⫻ 9 = 54; 7 ⫻ 9 = 63; 8 ⫻ 9 = 72; 9 ⫻ 9 = 81
2.
Compare the tens digit of each product with the multiplier of 9. What do you notice?
The tens digit of each product is 1 less than the
multiplier of 9.
3.
Add the digits in each product. What do you notice?
The digits in each product have a sum of 9.
Look at the pattern for multiplying a 1-digit number and 11.
1 ⫻ 11 = 11 2 ⫻ 11 = 22
4.
3 ⫻ 11 = 33
4 ⫻ 11 = 44
5 ⫻ 11 = 55
Use the pattern to predict the products of 7 ⫻ 11 and 9 ⫻ 11.
7 ⫻ 11 = 77; 9 ⫻ 11 = 99
Now look at the pattern for multiplying 11 by a 2-digit number whose digits have a sum
less than 10.
5.
11 ⫻ 11= 121
12 ⫻ 11 = 132
13 ⫻ 11 = 143
14 ⫻ 11 = 154
Compare the hundreds digit in each product with the tens digit in the multiplier of 11.
What do you notice?
They are the same.
6.
Compare the ones digit in each product with the ones digit in the multiplier of 11. What
do you notice?
They are the same.
7.
Compare the tens digit in each product with the sum of the digits in the multiplier of 11.
What do you notice?
They are the same.
8.
Use the pattern to predict the product: 15 ⫻ 11 =
24 ⫻ 11 =
54 ⫻ 11 =
264
594
32 ⫻ 11 =
63 ⫻ 11 =
352
693
165
41 ⫻ 11 =
18 ⫻ 11 =
451
198
Copyright © Houghton Mifflin Company. All rights reserved.
10 ⫻ 11 = 110