The Number System

Multiplying Decimals

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Objective: You will be able to…Multiply multi-digit decimals

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Multiplying Decimals Step 1:

Write the number with more digits Step 2:

Write the second number beneath the first; line up the DIGITS!

Step 3: Multiply the numbers normally

Step 4: Count the total number of digits after the decimals in the

problem Step 5:

Count the same number of digits in your answer (starting at the end of the number – count backwards)

Step 6: Put the decimal in front of the final digit you count

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Example 1

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Example 2

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You try 0.3 x 5.391

1.6173 23.41 x 6.5

152.165 1.88 x 365.3

686.784

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Mistakes What are some mistakes you think people

make when multiplying decimals? Lining up the decimals instead of the digits Putting the decimal in the wrong place in the

answer Why do you think they make those mistakes?

Adding & subtracting decimals have different rules How do you remember not to make those

mistakes?

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