2. Multiplication and Division 24 90 x 70 = 9 x 10 x 7 x 10 = 63 x 100 = 6300 90 x 4 = 9 x 10 x 4 = 36 x 10 = 360 3 x 70 = 7 x 10 x 3 = 70 x 3 = 210 3 x 4 = 12 6300 + 360 + 210 + 12 = 6882 93 x 74 = 90 + 3 6300 210 360 12 70 + 4

3. Multiplication and Division 24 1.Select cards to make two-digit numbers. 2.Multiply your numbers using place value and the distributive property in a table. Reflection: How can we multiply two-digit numbers? Problem Solving Toni bought 46 jellies for a party. Jellies cost 45 cents each. How much did Toni have to pay? Problem Solving 29 classes each have 24 children. How many children altogether? Investigation:

4. Multiplication and Division 24

5. Investigation: 1.Select cards to make a single-digit and a two-digit number. 2.Multiply your numbers using place value and the distributive property in a table. Reflection: How can we multiply two-digit numbers?

6. Multiplication and Division 24 Investigation: 1.Use a calculator to multiply a single-digit number by a two-digit number or 2 two-digit numbers.. 2.Check by multiplying your numbers using place value and the distributive property in a table. Reflection: How can we multiply two-digit numbers?

7. Multiplication and Division 24 Investigation: 1.Sit with a friend. 2.One child selects 4 cards to make a four-digit number. 3.Work out 2 two-digit numbers that would multiply to make a product close to the four-digit number. 4.Check by multiplying your numbers using place value and the distributive property in a table. 5.For example, you make the number 2856. You may suggest multiplying 31 by 99 because 28 times 100 would be just under 2856 so 31 x 99 might be just over. You may also suggest 62 x 49 because they have doubled 31 and almost halved 99. Reflection: How can we multiply two-digit numbers?

8. Multiplication and Division 24 Investigation: 1.Investigate other ways to multiply, for example, Ethiopian Multiplication Egyptian Multiplication Chinese Multiplication Russian Peasant method Asian Multiplication 2.Search YouTube for videos on these methods and explain why they work. Reflection: How do algorithms for multiplication and division use place value and properties and relationships?

9. Multiplication and Division 3 x 76 = 7 6 x 3 2 8 1

10. Multiplication and Division 43 x 76 = 7 6 x 4 3 2 8 1 2 3 0 4 0 3 2 6 8

11. 1.Select cards to make numbers you are ready to multiply using an algorithm. 2.Multiply the numbers, explain why your strategy is efficient. 3.Multiply using a calculator. Reflection: How do algorithms for multiplication use place value and properties and relationships? Investigation: Multiplication and Division Problem Solving There are 4 number cards. Use the number cards to make this algorithm true: Problem Solving What number makes this algorithm true?