Objective: Multiply a 2-digit number by a 2-digit number. Multiplication Objective: Multiply a 2-digit number by a 2-digit number.

Vocabulary * Product The answer to a multiplication problem. Factor A number that is multiplied by another number to find a product. Ex: 4 x 6 = 24, 4 and 6 are factors of 24 Multiply - The act of finding the total number of items in a given number of groups when each group contains the same number of items. It is a short cut for addition. Array An arrangement that shows objects in rows and columns. * Example:       3 x 4 = 12 3 4

Vocabulary continued * Set -a group of items. Times - to multiply. Multiple - the product of a whole number and any other number Ex: the multiples of 3 are 3, 6, 9, 12, 15. *

What multiplication number sentence can we use to represent this set of squares? 6 x 4 ------- 6 and 4 are the factors in this problem 24 product What word can we use to describe the arrangement of this set?

Practice 12 22 31 42 x 3 x 4 x 4 x 3 36 88 124 126 Find the product. 12 22 31 42 x 3 x 4 x 4 x 3 36 88 124 126 Demonstration http://www.dositey.com/muldiv/mul1ml1.htm Practice http://www.dositey.com/muldiv/mul1ss5.htm

Multiplication: 2 Digit by 2 Digit 27 x 38 -------

5 2 7 x 3 8 ------- 6 Multiply the numbers in the ones place. Regroup the 5 above the tens place. Put the 6 in the ones place of the product. 6

5 2 7 x 3 8 ------- 2 1 6 Multiply Diagonally The bottom ones digit times the top tens digit. Then you take this number and add the 5. 8 x 2 = 16 16+ 5 = 21 Put that answer in the tens place of the product. 5 2 7 x 3 8 ------- 2 1 6

5 2 7 x 3 8 ------- 2 1 6 Move to the 10’s Digit When you move to the bottom tens digit, you need to write a 0 below the ones digit of your answer (because you are now multiplying by a ten). 5 2 7 x 3 8 ------- 2 1 6

2 5 2 7 x 3 8 ------- 2 1 6 1 Multiplying by the 10’s Digit Multiply diagonally, the bottom tens digit by the top ones digit. 3 x 7 = 21 Carry the tens digit above the tens and write the ones digit beside the 0 in your answer. 5 2 7 x 3 8 ------- 2 1 6 1

2 5 2 7 x 3 8 ------- 2 1 6 8 1 Multiplying by the 10’s Digit Multiply straight up and down in the tens place 3 x 2 = 6…DON’T FORGET TO ADD THE 2! 6 + 2 = 8 Write the answer next to the 1 in your answer. 5 2 7 x 3 8 ------- 2 1 6 8 1

2 5 2 7 x 3 8 ------- 2 1 6 + 8 1 1 0 2 6 1 ALMOST DONE…now ADD Now…all you have to do is add the two lines of your answer! 2 1 6 + 8 1 0 1 0 2 6 5 2 7 x 3 8 ------- 1 2 1 6 + 8 1 1 0 2 6

Practice Find the product. 29 12 26 25 x43 x25 x65 x34 87 60 130 100 +1160 +240 +1560 +750 1247 300 1690 850

Review the vocabulary Product Multiplier Multiply Factor Set Array Times

TAKS Preparation Sample Questions

Mrs. Aljancic bought 14 bags of cookies Mrs. Aljancic bought 14 bags of cookies. There are 17 cookies in each bag. How many cookies did Mrs. Aljancic buy? 28 cookies 238 cookies 98 cookies 140 cookies

The fourth grade classes had a Browns party in the cafeteria The fourth grade classes had a Browns party in the cafeteria. There were 25 tables with 37 seats at each table. How many seats were there in all? 175 seats 750 seats 925 seats 185 seats

Mrs. Bell made 18 packages of cupcakes Mrs. Bell made 18 packages of cupcakes. There are 12 cupcakes in each package. Which number sentence shows how many cupcakes Mrs. Bell made? 18 + 12 18 - 12 18 x 12 18 x 2

A decagon has six sides. Mrs. Mason drew 10 decagons A decagon has six sides. Mrs. Mason drew 10 decagons. How many sides did she draw? Decagons 1 2 3 4 Sides 10 20 30 40 50 sides 20 sides 80 sides 100 sides

Miles Minutes 2 4 6 15 30 45 75 minutes 60 minutes 100 minutes The table shows how long it takes Mr. McFerren to ride his electric scooter. Miles Minutes 2 4 6 15 30 45 If this pattern continues, how many minutes will it take Mr. McFerren to ride 10 miles? 75 minutes 60 minutes 100 minutes 90 minutes