MULTIPLICATION Ms. Behling 3 rd grade math

STANDARD USED Represent and solve problems involving multiplication and division. CCSS.Math.Content.3.OA.A.1 CCSS.Math.Content.3.OA.A.1 Interpret products of whole numbers, e.g., interpret 5 × 7 as the total number of objects in 5 groups of 7 objects each. For example, describe a context in which a total number of objects can be expressed as 5 × 7.

WARM-UP What does ‘x’ mean in 2 x 3?

WARM-UP X=of 2 groups of 3 = 6 squares So, 2 x 3 = 6

PRODUCT What does the term product mean? When you multiply two numbers together, the answer is the “product” of those two numbers What is the product of 2 and 3? 6!

ORDER DOES NOT MATTER Commutative property of multiplication: factors can be multiplied in any order and the product is always the same For example: 4 x 2 = 8 AND 2 x 4 = 8 When else can we do this? Addition!

PATTERNS IN MULTIPLICATION: 0 When you multiply a number by zero, the product will always be zero 0 x 1 = 0 0 x 5 = 0 0 x 8 = 0

PATTERNS IN MULTIPLICATION: 1 When you multiply any number by 1, the product of the two numbers is itself 1 x 1 = 1 2 x 1 = 2 3 x 1 = 3 10 x 1 = x 1 = 564 Is this always going to be true?

PATTERNS IN MULTIPLICATION: 2 When you multiply a number by 2, the number doubles, as if you were adding it to itself. For example: 7 x 2 = 14 JUST LIKE = 14

PATTERNS IN MULTIPLICATION: 5 When you multiply a number by 5, the product will either end in a 5 or a 0. 5 x 1 = 5 5 x 2 = 10 5 x 3 = 15 5 x 4 = 20 5 x 5 = 25 5 x 6 = 30 5 x 7 = 35 5 x 8 = 40 5 x 9 = 45 5 x 10 = 50

PATTERNS IN MULTIPLICATION: 9 When multiplying a number by 9, hold up all 10 of your fingers with your palms facing away from you if you’re multiplying 2 x 9 then put down your second finger The fingers that are left on each side of the finger that is down gives you your answer For example with 2 x 9 when your second finger goes down, there is one finger left up to the left and 8 fingers left up to the right because 9 x 2 = 18

PATTERNS IN MULTIPLICATION: 10 When you multiply a number by 10, the product will be that number with a zero added to it 10 x 1 = x 2 = x 3 = x 4 = x 5 = x 6 = x 7 = x 8 = x 9 = x 10 = 100

PRACTICE Work on worksheet of practice problems with a partner When I ring the bell switch partners and keep working When I ring the bell a second time, go back to your seats and sit quietly

HOMEWORK Write out 15 multiplication problems for a classmate to solve tomorrow On another page write out an answer key for your own problems for you to turn in