Decimals

1
Decimals

• Chapter 4/5 Notes

2
Numbers

• The distance from the sun to Pluto is 3,600,000
  miles.
• A house dust mite can be as small as 0.0001
  meter.
• In Ch. 4, we will learn about the place value and
  scientific notation, which help us make sense out
  of numbers.

3
Place Value

• Lesson 1

4

• The planet Jupiter makes one trip around the sun
  every 11.8613 years.
• We read this numeral as eleven and eight
  thousand six hundred thirteen ten-thousandths.
  

5
Copy
6
Reading and Writing Decimals

• Lesson 2

7
4 Steps

1. Read the digits to the left of the decimal point
   as a whole number.
2. Say and for the for the decimal point
3. Read the digits to the right of the decimal point
   as a whole number.
4. Say the place name of the last digit.

8
For Example

• 23.415
• Twenty-three and four hundred fifteen thousandths

9
Your turn!

• 0.62

10
Comparing and Rounding Decimals

• Lesson 3

11
Which is bigger?

• You can tell which of two decimals is greater if
  you add zeros to the right of one of the decimal
  points.
• 24.428 and 24.43
• 24.428 and 24.430
• 24.428 lt 24.430

12
Your turn!

• 16.837 ___ 16.9
• 3.6 ___ 3.486
• 15.487 ___ 15.7

13
Scientific Notation

• Lesson 7

14

• A number between 1 and 10 multiplied by a power
  of 10, written as an exponent.
• 3,460,000. 3.46 x 106

15

• 26,000 2.6 x 104
• 425,000
• 630,000
• 2,000,000
• 21,000

16
Renaming Decimals as Fractions

• Lesson 9

17

• A decimal maybe renamed as a common fraction by
  using the digits in the numeral for the
  numerator.
• The denominator is the value of the last place
  name at the right of the numeral.

18
For Example

• 0.08 8 2 100 25
• 0.012 12 3 1,000 250

19
Your Turn!

• 0.82
• 0.5
• 0.208

20
Renaming Decimals as Fractions

• Lesson 10

21

• Some fractions can be renamed as decimals by
  changing the denominator to a power of 10.
• Like 10, 100, 1000

22
For Example

• 9 9 x 4 36 0.3625 25 x 4 100

23
Your Turn!

• 310
• 17100
• 1625

24
Decimals That Repeat

• Lesson 11

25

• Some fractions cant be changed to a decimal by
  raising the fraction to higher terms.
• You have to divide.

26

• Place zeros in the dividend until the digits in
  the quotient begin repeating.
• Draw a bar over the digits to show which digits
  repeat.

27
For Example

• __5/11 0.45
• (Divide 5 by 11)

28
Ratio and Proportion

• Chapter 5 Notes

29
Writing Ratios

• Lesson 1

30
Identifying Proportions

• Lesson 2

31
Solving Proportions

• Lesson 3

32
Using Proportions

• Lesson 4