Place ValueLesson #1

The name or symbol used to represent a number (#) is called a

Why do we need numbers?

NUMERAL

Numbers are Important!

Review: Ways of Comparing Numbers

You can list them in increasing or decreasing order

Plan them on a number line

Or use the > (greater than) or < (less than) symbols

Place Value:Each digit has a certain place value

Each place has a value of 10 times the place directly to its right

Place Values (before decimal)

Place Values (after decimal)

Face Value vs. Place Value

Face Value tells you how many ones, tens, or hundredths there are.

Face value is the actual value of the digit.

In the number 475, the "7" has a face value of 7.

Place value is what the digit represents IN ITS PLACE.

In the number 475, the "7" is in the tens place, so the place value is 70

Standard FormThe full number

The way you “normally” write a number

Expanded FormWriting a number showing the total place value of each digit

Example: 543

Placing the # into the Place Value Chart:

From the chart we see

100 x 5 = 500

10 x 4 = 40

1 x 3 = 3

Hundreds(100s)

Tens(10s)

Ones(1s)

500 40 3

So 543 in expanded form 5 x 100 + 4 x 10 + 3 x 1

Expanded Form with Decimals

Example: 48.25 Placing the # into the Place Value Chart:

From the chart we see

40 x 10 = 40

8 x 1 = 8

2 x 0.1 = 0.2

5 x 0.01 = 0.05

Tens(10)

Ones(1) DECIMAL Tenths

(0.1)Hundredths

(0.01)

40 8 . 2 5

So 48.25 in expanded form 4 x 10 + 8 x 1 + 2 x 0.1 + 5 x 0.01

Expanded Form: Practice

Complete the expanded form of the following numbers:

1) 384 = _______ + 8 x 10 + _______

2) 6257 = 6 x 1000 + ______ + ______ + ______

3) 37 = 10 x 3 + ________

4) 4826 = ________ + 100 x 8 + _______ + _____

5) 219.2 = ______ + _______ + ______ + ______

3 x100 + 8 x 10 + 4 x 1

6x1000 + 2x100 + 5x10 + 7x1

3 x 10 + 7 x1

4x1000 + 8x100 + 2x10 + 6x1

2x100 + 1x10 +9x1 + 2 x 0.1

What is the standard form of these expanded form numbers:

1) 800 + 40 + 3 =

2) 20 000 + 600 + 40 + 9 =

3) 1000 x 4 + 100 x 5 + 1 x 3 =

4) 100 x 9 + 1 x 8 + 0.1 x 5 =

Standard & Expanded Form:

Practice

843

20 649

4 503

908.5

For your notecard: PLACE VALUE & FORMS

ThousandsHundreds

TensOnes/Units

DECIMAL POINT Tenths

HundredthsThousandths

Standard form is how a number is normally written (543)

Expanded form shows each place value 543 = 5 x 100 + 4 x 10 +

3 x 148.25 = 4 x 10 + 8 x 1 + 2 x 0.1

+ 5 x 0.01

< less than > greater than

Homework! Complete the following questions in your workbook (this is a review of basic operations involving numbers)

p. 1, #1-3

p. 2 #4, 5, 8

p. 3 #9 + 10

p. 4 #11 (try the challenge question #13)

p. 5 #1-2

p. 6 #3-4