REPRESENTING, COMPARING, AND ORDERING DECIMALS

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V. EVERETT
SMS
6TH GRADE MATHEMATICS
NCSOS OBJECTIVE 1.03 AND 1.04
Tells us the meaning of a number
Example: $15 is more than $.15
Place value can help you understand and write
decimal numbers
You can compare numbers using place value
Example: 15.00
.15
a combination: a whole number and a number
in between whole numbers
represent the numbers in between whole
number.
Numbers that have a decimal point
To read decimals
I. Read the whole number
II. Read the decimal as “and”
III. Read the number after the decimal and its place
value
Example:
a) 3.16 is read as three and sixteen hundredths
b) 14.011 is read as fourteen and eleven
thousandths
c) 0.69 is read as sixty-nine hundredths
THREE FORMS:
Standard: 2015.05
Expanded: 2000 + 10 + 5 + 0.05
Word: two thousand fifteen and five hundredths
If you can say it, you can write it!!
Tips for writing in expanded form
Write the number that appears before the decimal point in expanded form.
For decimals, place a zero in the ones place.
Also, substitute zeroes for all spaces after the decimal point that come before
the digit that you are working with.
Standard
form
0.085
Expanded form
Word form
90000 + 800 + 10 + 3 +
0.07 + 0.006 + 0.0005
Ten and forty one hundredths
400 + 50 + 2 + 0.7 +
0.09 + 0.002
86,945.56
Four thousand nine hundred
ninety one and six tenths
If you are comparing tenths to hundredths, you can use a
tenths grid and a hundredths grid. Here, you can see
that 0.4 is greater than 0.36.
There is a simple way to compare decimals!!
( just like comparing whole numbers)
1. Line up the numbers vertically by the decimal
point.
2. Add “0” to fill in any missing spaces.
3. Compare from left to right.
Use >, <, or = to compare decimals
Example: 12.36 ___ 12.24
Step 1: 12.36
12.24
Step 2: no zeros needed
Step 3: the same digits are in the tens and ones
place
In the tenths place 3 is bigger than 2.
So 12.36 is greater than 12.24
Answer: 12.36 >12.24
1)0.9 ____0.875
2)3.65 ____3.589
3)9.09____9.2
4)3.099____3.1
TWO WAYS TO ORDER
ASCENDING
DESCENDING
LEAST TO GREATEST
GREATEST TO LEAST
USE THE SAME METHOD FOR COMPARING TO
ORDER DECIMALS
Put these numbers in ASCENDING order:
12.5; 12.24; 11.96; 12.36
12.50
12.24
11.96
12.36
ANSWER: 11.96, 12.24, 12.36, 12.5
PUT IN DESCENDING ORDER:
14.35, 14.3, 14.05, 14.354, 14.39
CLASSWORK:
PRACTICE 1-2 AND 1-3 ODDS ONLY
HOMEWORK:
RETEACHING 1-2 AND 1-3 EVENS ONLY
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