Transcript Divide with decimals - Nadaburg Unified School District #81

Divide 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.
Essential Questions
1.
What is addition? How do you add decimals?
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 divide whole
numbers....
Take turns with your face partner and describe
how we multiply and divide whole numbers.
Objective
I can divide decimals to hundredths place.
Let’s
Decimal - a number
with aReview
fractionAgain
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.
24.56 x 4 . 1 = 100.696
Rules for Dividing Decimals
To divide decimals, divide as you
would with a normal whole number
then you move over the decimal.
Dividing Decimals
Example 2
Solve = 2.25 ÷ 2.5
2.5)2.25
Divisor
Estimate, Multiply, Subtract, Bring
Down, Start again/Stop
Dividend
Dividing Decimals
Example 2
Solve = 2.25 ÷ 2.5
0
2.5)2.25
-0
225
Divide as with whole numbers.
Dividing Decimals
Example 2
Solve = 2.25 ÷ 2.5
0.9
25)22.5
-0
225
-225
0
Answer: 0.9
Divide as with whole numbers.
Move decimal from 2.5 (divisor)
over 1 to “get rid of it”
Move the decimal over that same
amount of spaces in the dividend.
Then move decimal straight up.
Now let’s try one together
.46 ÷ 1.2
Now you do one
15.2 ÷ 4.1
Lesson on Dividing
Decimals
http://learnzillion.com/lessons/561-dividedecimals-using-knowledge-of-multiplication
You and a partner try...
Using what you learned in the lesson, using
pictures, models, and properties of operations
solve this problem with your partner...
26.4 ÷ .03
Closure
Think about what is different about dividing whole
numbers and dividing decimals
Write a $2 summary explaining what is different
Repeat todays objective
Let’s watch a fun video
about dividing decimals
http://www.youtube.com/watch/?v=iWU6K3GV2A8
Independent Practice!!! (yay)
1) 1.269 ÷ .03 =
2) 25.505 ÷ 05 =
3) .1824 ÷ .6 =
4) 243.6 ÷ 1.2 =
5) 18.72 ÷ .9 =
6) 50.70 ÷ 1.0 =
7) 168.56 ÷ .08 =
8) 48.164 ÷ .4 =