 Multiply with decimals

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Multiply with decimals
Standard UW.GAP.5.M.NBT.07 Add, subtract, multiply, and divide decimals to hundredths using concrete models or drawing and strategies based on place value, properties of operations, and/or the relationship between addition and subtraction; relate the strategy to a written method and explain the reasoning used.

2. What is subtraction? How do you subtract decimals? 3. What is multiplication? How do you use a model and partial products to represent multiplying decimals? 4. What is division? How do you use a model and partial products to represent dividing decimals?

Set.... Think about the strategies we use to multiply whole numbers.... Take turns with your face partner and describe how we multiply and divide whole numbers.

Objective: I can multiply decimals to hundredths place.

Let’s Review Decimal - a number with a fraction of tenths, hundredths, etc. written after a decimal point. Decimal point - the (.) between a whole number and fractions of tenths, hundredths, thousandths, etc. Digit- any of the numerals 0-9, which may be part of a larger number. x =

Think back to Adding and Subtracting Decimals
Step 1- line up the decimals Step 2- add any place holding zeros Step 3 - add or subtract like you always do Step 4 - bring the decimal straight down Multiplication is much different, let’s learn how...

Rules for Multiplying Decimals
When multiplying decimals, multiply just like normal then move decimal over to the right, then move decimal that many place in answer to the left.

Multiplying Decimals Example 1 Solve = 10.7 x 0.13 10.7
1 decimal place

Multiplying Decimals Example 1 Solve = 10.7 x 0.13 10.7 x0.13
1 decimal place 2 decimal places

Multiplying Decimals Example 1 Solve = 10.7 x 0.13 10.7 x0.13 321
1 decimal place 2 decimal places

Multiplying Decimals Example 1 Solve = 10.7 x 0.13 10.7 x0.13 321
1070 1 decimal place 2 decimal places

Multiplying Decimals Example 1 Solve = 10.7 x 0.13 10.7 x0.13
321 +1070 1.391 1 decimal place 2 decimal places 3 decimal places

Let’s watch how to multiply with models

Let’s try one together... 4.56 x .83

Now you try 16.73 x 4.89

Closure Think about what is different about multiplying whole numbers and multiplying decimals On your slate: Write a \$2 summary explaining what is different Repeat todays objective

Independent Practice 1. 45.2 x 2.3= 2. 98.01 x 7= 3. 6.6 x 4.9