copyright 2011 Creative Smarts Inc

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2 x Greg Tang s x Greg Tang s x Greg Tang s Great Times TM Series Overview Multiplication Worksheets &'$()!"#$% Multiplication Worksheets Greg Tang s LEARNING the Basic Times Tables &'$()!"#$% Multiplication Worksheets volume 1 Greg Tang s Extending extending the Basic Times Tables &'$() volume 3 Multiplication Worksheets Greg Tang s mastering Mastering the Basic Times Tables volume 2 Wouldn t it be great if there were a better way for kids to learn their multiplication facts instead of brute force memorization? If there were a systematic approach that develops true understanding, improves number sense and develops the abstract, algebraic thinking skills needed for higher math? Well there is! Greg Tang s three-part multiplication series builds on the revolutionary strategies he first introduced in his best-selling picture book The Best of Times and made even more popular with his Great Times TM multiplication flash cards. Now, Greg offers a series of worksheets that provides the instruction, practice and rigor kids need to truly master multiplication. In part 1 of the series, Learning the Basic Times Tables, students take the first step in learning multiplication by thinking and adding in smart groups. Greg s common sense approach teaches basic multiplication facts while laying the groundwork for larger numbers. In part 2, Mastering the Basic Times Tables, students take the important next step by moving away from addition and learning to think more efficiently using partial products to multiply. Just as addition evolves from counting, multiplication evolves from addition. In part 3 of the series, Beyond the Basic Times Tables, students learn to extend and apply partial products to doubledigit numbers. Being good at multiplication means being able to multiply all numbers, not just small numbers. By applying smart grouping strategies more generally, students also learn to think algebraically the key to being good in math. copyright 2011 Creative Smarts Inc 1

3 Table of Contents Beyond the Basic Times Tables Overview page 3 How It Works page 4 Partial Products (on paper) Multiply numbers from pages 5-10 Multiply numbers from pages Multiply numbers from pages Multiply numbers from pages Partial Products (mental math) Multiply numbers from pages Multiply numbers from pages Multiply numbers from pages Multiply numbers from pages Practice & Assessment Grouping Practice pages Assessment 1-10: Single x Double-digit (on paper)..... pages Assessment 11-20: Double x Single-digit (on paper)..... pages Assessment 21-30: Single x Double-digit (mental math)..... pages Assessment 31-40: Double x Single-digit (mental math).... pages Timed Tests pages Answer Key pages copyright 2011 Creative Smarts Inc 2

4 Overview In Beyond the Basic Times Tables, students take the first step in learning to multiply bigger numbers by applying partial products to double-digit numbers. There are several important benefits. First, since single-digit multiplication is used to multiply doubledigit numbers, students get more practice with their basic facts. Second, they get the obvious benefit of learning to multiply numbers of any size. Most kids can only work with small numbers, which is one of the reasons they struggle with math as they get older. Third, students learn to think algebraically. The ability to think more generally and apply specific strategies to a wide range of problems and situations is the key to being a good problem solver. To multiply bigger numbers, students learn to first break apart numbers into smaller, more manageable parts. The next step is to apply the distributive property and multiply the parts. For example, to multiply 4 x 17, first break 17 into 10 Then multiply 4 x 10 = 40 and 4 x 7 = 2 The sum of these partial products is the total product or answer, so 4 x 17 = = 6 Algebraically, the distributive property can be written as: a x (b c) = (a x b) ( a x c). This extremely important property is the key to working with big numbers and complex equations. Sequence. With these worksheets, students will learn to solve two kinds of double-digit multiplication problems: single-digit numbers times double-digit numbers and doubledigit numbers times single-digit numbers. The double-digit numbers range from 11 to 20, but the same concepts can be applied more generally to numbers of any size. Format. A simple horizontal format is used to help students visualize and apply the distributive property. Initially, students write out the partial products to make computations easier, but subsequently they must do everything in their heads rather than on paper.. Being good at mental math is critical to developing strong math skills. Distributive Property 4 x 17 4 x (107) = (4x10) (4x7) 4 x 17 = 68 Assessment. To gain practice and give teachers and parents a chance to assess their skills, students apply individual strategies first to a single number at a time and then more generally to different numbers. True mastery means being able to multiply any number in any order both quickly and correctly. copyright 2011 Creative Smarts Inc 3

5 How It Works Multiplication strategies are presented in sequential order, starting with 0 and progressing up to 20. Single-digit numbers are multiplied by double-digit numbers, then double-digit numbers by single-digit numbers. Since it is helpful for students learning a new strategy to write down intermediate steps, the worksheets begin by asking for both partial products and the total product or answer. Write out partial products Final answer 4 x 17 (4x10) (4x7) = x 17 = 68 Once students are familiar with a strategy and can solve problems when they write out the partial products, the next step is to do the entire calculation in their heads. Worksheets that ask only for the final answer help develop good mental math skills. Do entire calculation mentally Final answer 4 x 17 (4x10) (4x7) 4 x 17 = 68 After mastering specific strategies, students are asked to think more generally by applying different strategies first to one number at a time and then to various numbers in any order. These worksheets give students much-needed practice and give teachers and parents the opportunity to assess their skills and understanding. Apply distributive property Final answer 3 x 16 (3x10) (3x6) 3 x 16 = 48 7 x 13 (7x10) (7x3) 7 x 13 = 91 6 x 12 (6x10) (6x2) 6 x 12 = 72 The final worksheets use a traditional problem-answer format and no grouping strategies are provided. Students must be able to look at a problem, apply the distributive property, and do all the necessary calculations quickly and correctly in their heads. With practice, double-digit multiplication is fun, fast and easy! 15 x 8 = x 19 = x 9 = 162 copyright 2011 Creative Smarts Inc 4

6 Multiply by 0 A group of 0 s quickly done no matter what the answer s none! 0 times any number is zero. This is also known as the zero property of multiplication. 0 x 16 = a group of 0 16s = 0 0 x 15 a group of 15s 0 x 15 = 0 x 14 a group of 14s 0 x 14 = 0 x 11 a group of 11s 0 x 11 = 0 x 13 a group of 13s 0 x 13 = 0 x 12 a group of 12s 0 x 12 = 0 x 18 a group of 18s 0 x 18 = 0 x 16 a group of 16s 0 x 16 = 0 x 19 a group of 19s 0 x 19 = 0 x 17 a group of 17s 0 x 17 = 0 x 20 a group of 20s 0 x 20 = Copyright 2011 Creative Smarts Inc 5

7 Multiply by 1 A group of 1 you won t forget what you see is what you get! 1 times any number is the number itself. 1 is also called the multiplicative identity. 1 x 15 = a group of 1 15 = 15 1 x 15 a group of 15 1 x 15 = 1 x 14 a group of 14 1 x 14 = 1 x 11 a group of 11 1 x 11 = 1 x 13 a group of 13 1 x 13 = 1 x 12 a group of 12 1 x 12 = 1 x 18 a group of 18 1 x 18 = 1 x 16 a group of 16 1 x 16 = 1 x 19 a group of 19 1 x 19 = 1 x 17 a group of 17 1 x 17 = 1 x 20 a group of 20 1 x 20 = Copyright 2011 Creative Smarts Inc 6

8 Multiply by 2 Write out the partial products then add them in your head. To multiply 2 times a double-digit number, break the number into two parts. Multiply 2 times the first part then 2 times the second part. Add these partial products to get the total product. 2 x 17 = (2 x 10) (2 x 7) = = 34 2 x 15 (2x10) (2x5) = 2 x 15 = 2 x 14 (2x10) (2x4) = 2 x 14 = 2 x 11 (2x10) (2x1) = 2 x 11 = 2 x 13 (2x10) (2x3) = 2 x 13 = 2 x 12 (2x10) (2x2) = 2 x 12 = 2 x 18 (2x10) (2x8) = 2 x 18 = 2 x 16 (2x10) (2x6) = 2 x 16 = 2 x 19 (2x10) (2x9) = 2 x 19 = 2 x 17 (2x10) (2x7) = 2 x 17 = 2 x 20 (2x10) (2x10) = 2 x 20 = Copyright 2011 Creative Smarts Inc 7

12 Multiply by 6 Write out the partial products then add them in your head. To multiply 6 times a double-digit number, break the number into two parts. Multiply 6 times the first part then 6 times the second part. Add these partial products to get the total product. 6 x 17 = (6 x 10) (6 x 7) = = x 15 (6x10) (6x5) = 6 x 15 = 6 x 14 (6x10) (6x4) = 6 x 14 = 6 x 11 (6x10) (6x1) = 6 x 11 = 6 x 13 (6x10) (6x3) = 6 x 13 = 6 x 12 (6x10) (6x2) = 6 x 12 = 6 x 18 (6x10) (6x8) = 6 x 18 = 6 x 16 (6x10) (6x6) = 6 x 16 = 6 x 19 (6x10) (6x9) = 6 x 19 = 6 x 17 (6x10) (6x7) = 6 x 17 = 6 x 20 (6x10) (6x10) = 6 x 20 = Copyright 2011 Creative Smarts Inc 11

17 Multiply by 11 Write out the partial products then add them in your head. A group of 11 is a group of 10 plus a group of So 11 times a number is 10 times the number plus 1 times the number. The sum of the partial products is the total product or answer. 11 x 7 = (10 x 7) (1 x 7) = 70 7 = x 5 (10x5) (1x5) = 11 x 5 = 11 x 4 (10x4) (1x4) = 11 x 4 = 11 x 1 (10x1) (1x1) = 11 x 1 = 11 x 3 (10x3) (1x3) = 11 x 3 = 11 x 2 (10x2) (1x2) = 11 x 2 = 11 x 8 (10x8) (1x8) = 11 x 8 = 11 x 6 (10x6) (1x6) = 11 x 6 = 11 x 9 (10x9) (1x9) = 11 x 9 = 11 x 7 (10x7) (1x7) = 11 x 7 = 11 x 10 (10x10) (1x10) = 11 x 10 = Copyright 2011 Creative Smarts Inc 16

18 Multiply by 12 Write out the partial products then add them in your head. 12 times a number is 10 times the number plus 2 times the number. The sum of these partial products is the total product or answer. 12 x 7 = (10 x 7) (2 x 7) = = x 5 (10x5) (2x5) = 12 x 5 = 12 x 4 (10x4) (2x4) = 12 x 4 = 12 x 1 (10x1) (2x1) = 12 x 1 = 12 x 3 (10x3) (2x3) = 12 x 3 = 12 x 2 (10x2) (2x2) = 12 x 2 = 12 x 8 (10x8) (2x8) = 12 x 8 = 12 x 6 (10x6) (2x6) = 12 x 6 = 12 x 9 (10x9) (2x9) = 12 x 9 = 12 x 7 (10x7) (2x7) = 12 x 7 = 12 x 10 (10x10) (2x10) = 12 x 10 = Copyright 2011 Creative Smarts Inc 17

21 Multiply by 15 Write out the partial products then add them in your head. 15 times a number is 10 times the number plus 5 times the number. The sum of these partial products is the total product or answer. Hint: remember 5 is half of 10! 15 x 7 = (10 x 7) (5 x 7) = = x 5 (10x5) (5x5) = 15 x 5 = 15 x 4 (10x4) (5x4) = 15 x 4 = 15 x 1 (10x1) (5x1) = 15 x 1 = 15 x 3 (10x3) (5x3) = 15 x 3 = 15 x 2 (10x2) (5x2) = 15 x 2 = 15 x 8 (10x8) (5x8) = 15 x 8 = 15 x 6 (10x6) (5x6) = 15 x 6 = 15 x 9 (10x9) (5x9) = 15 x 9 = 15 x 7 (10x7) (5x7) = 15 x 7 = 15 x 10 (10x10) (5x10) = 15 x 10 = Copyright 2011 Creative Smarts Inc 20

27 Multiply by 2 Now do everything in your head! To multiply 2 times a double-digit number, break the number into two parts. Multiply 2 times the first part then 2 times the second part. Add these partial products to get the total product. 2 x 17 = (2 x 10) (2 x 7) = = 34 2 x 15 (2x10) (2x5) 2 x 15 = 2 x 14 (2x10) (2x4) 2 x 14 = 2 x 11 (2x10) (2x1) 2 x 11 = 2 x 13 (2x10) (2x3) 2 x 13 = 2 x 12 (2x10) (2x2) 2 x 12 = 2 x 18 (2x10) (2x8) 2 x 18 = 2 x 16 (2x10) (2x6) 2 x 16 = 2 x 19 (2x10) (2x9) 2 x 19 = 2 x 17 (2x10) (2x7) 2 x 17 = 2 x 20 (2x10) (2x10) 2 x 20 = Copyright 2011 Creative Smarts Inc 26

31 Multiply by 6 Now do everything in your head! To multiply 6 times a double-digit number, break the number into two parts. Multiply 6 times the first part then 6 times the second part. Add these partial products to get the total product. 6 x 17 = (6 x 10) (6 x 7) = = x 15 (6x10) (6x5) 6 x 15 = 6 x 14 (6x10) (6x4) 6 x 14 = 6 x 11 (6x10) (6x1) 6 x 11 = 6 x 13 (6x10) (6x3) 6 x 13 = 6 x 12 (6x10) (6x2) 6 x 12 = 6 x 18 (6x10) (6x8) 6 x 18 = 6 x 16 (6x10) (6x6) 6 x 16 = 6 x 19 (6x10) (6x9) 6 x 19 = 6 x 17 (6x10) (6x7) 6 x 17 = 6 x 20 (6x10) (6x10) 6 x 20 = Copyright 2011 Creative Smarts Inc 30

36 Multiply by 11 Now do everything in your head! 11 times a number is 10 times the number plus 1 times the number. The sum of these partial products is the total product or answer. 11 x 7 = (10 x 7) (1 x 7) = 70 7 = x 5 (10x5) (1x5) 11 x 5 = 11 x 4 (10x4) (1x4) 11 x 4 = 11 x 1 (10x1) (1x1) 11 x 1 = 11 x 3 (10x3) (1x3) 11 x 3 = 11 x 2 (10x2) (1x2) 11 x 2 = 11 x 8 (10x8) (1x8) 11 x 8 = 11 x 6 (10x6) (1x6) 11 x 6 = 11 x 9 (10x9) (1x9) 11 x 9 = 11 x 7 (10x7) (1x7) 11 x 7 = 11 x 10 (10x10) (1x10) 11 x 10 = Copyright 2011 Creative Smarts Inc 35

37 Multiply by 12 Now do everything in your head! 12 times a number is 10 times the number plus 2 times the number. The sum of these partial products is the total product or answer. 12 x 7 = (10 x 7) (2 x 7) = = x 5 (10x5) (2x5) 12 x 5 = 12 x 4 (10x4) (2x4) 12 x 4 = 12 x 1 (10x1) (2x1) 12 x 1 = 12 x 3 (10x3) (2x3) 12 x 3 = 12 x 2 (10x2) (2x2) 12 x 2 = 12 x 8 (10x8) (2x8) 12 x 8 = 12 x 6 (10x6) (2x6) 12 x 6 = 12 x 9 (10x9) (2x9) 12 x 9 = 12 x 7 (10x7) (2x7) 12 x 7 = 12 x 10 (10x10) (2x10) 12 x 10 = Copyright 2011 Creative Smarts Inc 36

40 Multiply by 15 Now do everything in your head! 15 times a number is 10 times the number plus 5 times the number. The sum of these partial products is the total product or answer. Hint: remember 5 is half of 10! 15 x 7 = (10 x 7) (5 x 7) = = x 5 (10x5) (5x5) 15 x 5 = 15 x 4 (10x4) (5x4) 15 x 4 = 15 x 1 (10x1) (5x1) 15 x 1 = 15 x 3 (10x3) (5x3) 15 x 3 = 15 x 2 (10x2) (5x2) 15 x 2 = 15 x 8 (10x8) (5x8) 15 x 8 = 15 x 6 (10x6) (5x6) 15 x 6 = 15 x 9 (10x9) (5x9) 15 x 9 = 15 x 7 (10x7) (5x7) 15 x 7 = 15 x 10 (10x10) (5x10) 15 x 10 = Copyright 2011 Creative Smarts Inc 39

46 Practice Grouping 2s Practice grouping 2s in groups ranging in size from 11 to 20. This contrasts with finding 2 times a number, which means putting numbers into groups of Example. 15 x 2 means a group of fifteen 2s 2 x 15 means a group of 2 fifteens 11 x 2 (10x2) (1x2) = 11 x 2 = 12 x 2 (10x2) (2x2) = 12 x 2 = 13 x 2 (10x2) (3x2) = 13 x 2 = 14 x 2 (10x2) (4x2) = 14 x 2 = 15 x 2 (10x2) (5x2) = 15 x 2 = 16 x 2 (10x2) (6x2) = 16 x 2 = 17 x 2 (10x2) (7x2) = 17 x 2 = 18 x 2 (10x2) (8x2) = 18 x 2 = 19 x 2 (10x2) (9x2) = 19 x 2 = 20 x 2 (10x2) (10x2) = 20 x 2 = Copyright 2011 Creative Smarts Inc 45

47 Practice Grouping 3s Practice grouping 3s in groups ranging in size from 11 to 20. This contrasts with finding 3 times a number, which means putting numbers into groups of Example. 16 x 3 means a group of sixteen 3s 3 x 16 means a group of 3 sixteens 11 x 3 (10x3) (1x3) = 11 x 3 = 12 x 3 (10x3) (2x3) = 12 x 3 = 13 x 3 (10x3) (3x3) = 13 x 3 = 14 x 3 (10x3) (4x3) = 14 x 3 = 15 x 3 (10x3) (5x3) = 15 x 3 = 16 x 3 (10x3) (6x3) = 16 x 3 = 17 x 3 (10x3) (7x3) = 17 x 3 = 18 x 3 (10x3) (8x3) = 18 x 3 = 19 x 3 (10x3) (9x3) = 19 x 3 = 20 x 3 (10x3) (10x3) = 20 x 3 = Copyright 2011 Creative Smarts Inc 46

48 Practice Grouping 4s Practice grouping 4s in groups ranging in size from 11 to 20. This contrasts with finding 4 times a number, which means putting numbers into groups of Example. 18 x 4 means a group of eighteen 4s 4 x 18 means a group of 4 eighteens Think Think Multiplication Quick 11 x 4 (10x4) (1x4) = 11 x 4 = 12 x 4 (10x4) (2x4) = 12 x 4 = 13 x 4 (10x4) (3x4) = 13 x 4 = 14 x 4 (10x4) (4x4) = 14 x 4 = 15 x 4 (10x4) (5x4) = 15 x 4 = 16 x 4 (10x4) (6x4) = 16 x 4 = 17 x 4 (10x4) (7x4) = 17 x 4 = 18 x 4 (10x4) (8x4) = 18 x 4 = 19 x 4 (10x4) (9x4) = 19 x 4 = 20 x 4 (10x4) (10x4) = 20 x 4 = Copyright 2011 Creative Smarts Inc 47

49 Practice Grouping 5s Practice grouping 5s in groups ranging in size from 11 to 20. This contrasts with finding 5 times a number, which means putting numbers into groups of Example. 12 x 5 means a group of 12 fives 5 x 12 means a group of 5 twelves 11 x 5 (10x5) (1x5) = 11 x 5 = 12 x 5 (10x5) (2x5) = 12 x 5 = 13 x 5 (10x5) (3x5) = 13 x 5 = 14 x 5 (10x5) (4x5) = 14 x 5 = 15 x 5 (10x5) (5x5) = 15 x 5 = 16 x 5 (10x5) (6x5) = 16 x 5 = 17 x 5 (10x5) (7x5) = 17 x 5 = 18 x 5 (10x5) (8x5) = 18 x 5 = 19 x 5 (10x5) (9x5) = 19 x 5 = 20 x 5 (10x5) (10x5) = 20 x 5 = Copyright 2011 Creative Smarts Inc 48

50 Practice Grouping 6s Practice grouping 6s in groups ranging in size from 11 to 20. This contrasts with finding 6 times a number, which means putting numbers into groups of Example. 13 x 6 means a group of thirteen 6s 6 x 13 means a group of 6 thirteens 11 x 6 (10x6) (1x6) = 11 x 6 = 12 x 6 (10x6) (2x6) = 12 x 6 = 13 x 6 (10x6) (3x6) = 13 x 6 = 14 x 6 (10x6) (4x6) = 14 x 6 = 15 x 6 (10x6) (5x6) = 15 x 6 = 16 x 6 (10x6) (6x6) = 16 x 6 = 17 x 6 (10x6) (7x6) = 17 x 6 = 18 x 6 (10x6) (8x6) = 18 x 6 = 19 x 6 (10x6) (9x6) = 19 x 6 = 20 x 6 (10x6) (10x6) = 20 x 6 = Copyright 2011 Creative Smarts Inc 49

51 Practice Grouping 7s Practice grouping 7s in groups ranging in size from 11 to 20. This contrasts with finding 7 times a number, which means putting numbers into groups of Example. 14 x 7 means a group of fourteen 7s 7 x 14 means a group of 7 fourteens 11 x 7 (10x7) (1x7) = 11 x 7 = 12 x 7 (10x7) (2x7) = 12 x 7 = 13 x 7 (10x7) (3x7) = 13 x 7 = 14 x 7 (10x7) (4x7) = 14 x 7 = 15 x 7 (10x7) (5x7) = 15 x 7 = 16 x 7 (10x7) (6x7) = 16 x 7 = 17 x 7 (10x7) (7x7) = 17 x 7 = 18 x 7 (10x7) (8x7) = 18 x 7 = 19 x 7 (10x7) (9x7) = 19 x 7 = 20 x 7 (10x7) (10x7) = 20 x 7 = Copyright 2011 Creative Smarts Inc 50

52 Practice Grouping 8s Practice grouping 8s in groups ranging in size from 11 to 20. This contrasts with finding 8 times a number, which means putting numbers into groups of Example. 12 x 8 means a group of twelve 8s 8 x 12 means a group of 8 twelves 11 x 8 (10x8) (1x8) = 11 x 8 = 12 x 8 (10x8) (2x8) = 12 x 8 = 13 x 8 (10x8) (3x8) = 13 x 8 = 14 x 8 (10x8) (4x8) = 14 x 8 = 15 x 8 (10x8) (5x8) = 15 x 8 = 16 x 8 (10x8) (6x8) = 16 x 8 = 17 x 8 (10x8) (7x8) = 17 x 8 = 18 x 8 (10x8) (8x8) = 18 x 8 = 19 x 8 (10x8) (9x8) = 19 x 8 = 20 x 8 (10x8) (10x8) = 20 x 8 = Copyright 2011 Creative Smarts Inc 51

53 Practice Grouping 9s Practice grouping 9s in groups ranging in size from 11 to 20. This contrasts with finding 9 times a number, which means putting numbers into groups of Example. 13 x 9 means a group of thirteen 9s 9 x 13 means a group of 9 thirteens 11 x 9 (10x9) (1x9) = 11 x 9 = 12 x 9 (10x9) (2x9) = 12 x 9 = 13 x 9 (10x9) (3x9) = 13 x 9 = 14 x 9 (10x9) (4x9) = 14 x 9 = 15 x 9 (10x9) (5x9) = 15 x 9 = 16 x 9 (10x9) (6x9) = 16 x 9 = 17 x 9 (10x9) (7x9) = 17 x 9 = 18 x 9 (10x9) (8x9) = 18 x 9 = 19 x 9 (10x9) (9x9) = 19 x 9 = 20 x 9 (10x9) (10x9) = 20 x 9 = Copyright 2011 Creative Smarts Inc 52

54 Practice Grouping 10s Practice grouping 10s in groups ranging in size from 11 to 20. This contrasts with finding 10 times a number, which means putting numbers into groups of Example. 14 x 10 means a group of fourteen 10s 10 x 14 means a group of 10 fourteens 11 x 10 (10x10) (1x10) = 11 x 10 = 12 x 10 (10x10) (2x10) = 12 x 10 = 13 x 10 (10x10) (3x10) = 13 x 10 = 14 x 10 (10x10) (4x10) = 14 x 10 = 15 x 10 (10x10) (5x10) = 15 x 10 = 16 x 10 (10x10) (6x10) = 16 x 10 = 17 x 10 (10x10) (7x10) = 17 x 10 = 18 x 10 (10x10) (8x10) = 18 x 10 = 19 x 10 (10x10) (9x10) = 19 x 10 = 20 x 10 (10x10) (10x10) = 20 x 10 = Copyright 2011 Creative Smarts Inc 53

55 Practice Grouping 11s Practice grouping 11s in groups ranging in size from 1 to This contrasts with finding 11 times a number, which means putting numbers into groups of 1 Example. 5 x 11 means a group of five 11s 11 x 5 means a group of 11 fives 1 x 11 (1x10) (1x1) = 1 x 11 = 2 x 11 (2x10) (2x1) = 2 x 11 = 3 x 11 (3x10) (3x1) = 3 x 11 = 4 x 11 (4x10) (4x1) = 4 x 11 = 5 x 11 (5x10) (5x1) = 5 x 11 = 6 x 11 (6x10) (6x1) = 6 x 11 = 7 x 11 (7x10) (7x1) = 7 x 11 = 8 x 11 (8x10) (8x1) = 8 x 11 = 9 x 11 (9x10) (9x1) = 9 x 11 = 10 x 11 (10x10) (10x1) = 10 x 11 = Copyright 2011 Creative Smarts Inc 54

64 Practice Grouping 20s Practice grouping 20s in groups ranging in size from 1 to This contrasts with finding 20 times a number, which means putting numbers into groups of 20. Example. 5 x 20 means a group of five 20s 20 x 5 means a group of 20 fives 1 x 20 (1x10) (1x10) = 1 x 20 = 2 x 20 (2x10) (2x10) = 2 x 20 = 3 x 20 (3x10) (3x10) = 3 x 20 = 4 x 20 (4x10) (4x10) = 4 x 20 = 5 x 20 (5x10) (5x10) = 5 x 20 = 6 x 20 (6x10) (6x10) = 6 x 20 = 7 x 20 (7x10) (7x10) = 7 x 20 = 8 x 20 (8x10) (8x10) = 8 x 20 = 9 x 20 (9x10) (9x10) = 9 x 20 = 10 x 20 (10x10) (10x10) = 10 x 20 = Copyright 2011 Creative Smarts Inc 63

65 Assessment 1 Mastery of basic multiplication facts means being able to both quickly recall and quickly derive every answer. This requires a lot of practice and hard work, so practice these worksheets until you can do them fast! 6 x 12 (6x10) (6x2) = 6 x 12 = 9 x 13 (9x10) (9x3) = 9 x 13 = 5 x 20 (5x10) (5x10) = 5 x 20 = 1 x 16 (1x10) (1x6) = 1 x 16 = 4 x 19 (4x10) (4x9) = 4 x 19 = 7 x 14 (7x10) (7x4) = 7 x 14 = 3 x 17 (3x10) (3x7) = 3 x 17 = 8 x 15 (8x10) (8x5) = 8 x 15 = 2 x 11 (2x10) (2x1) = 2 x 11 = 10 x 18 (10x10) (10x8) = 10 x 18 = Copyright 2011 Creative Smarts Inc 64