“I’m Thinking of a Number”
 My number has three digits to the right of
the decimal point.
 My number is greater than 4.6 and less than
4.7.
 My number contains a 4 with a value equal
to 4 x 1/100.
 My number has a 9 in the thousandths
place.
 What is my number?
Number Forms
What are some
different ways you can
think of to write the
number 4,358?
Number Forms
 Base Ten Numeral (Standard Form): 4,358
 Number Name (Word Form): four thousand
three hundred fifty-eight
 Expanded Form: 4,000 + 300 + 50 + 8
How would you write 124.659
in all three forms?
Decimal Forms
 Base Ten Numeral (Standard form):
124.659
 Number Name (Word Form): one hundred
twenty four AND six hundred fifty nine
thousandths
 Expanded form: 100 + 20 + 4 + 6 x (1/10) +
5 x (1/100) + 9 x (1/1000)
 When might you use number names?
 When might you use base ten
numerals?
 When might you use expanded form?
 What is the purpose of using expanded
form?
Let’s Practice!
Working in teams, write each number in all
three forms:
765
2.334
5,378,402
9,467.009
765
(7x100) + (6x10) + (5x1)
seven hundred sixty-five
2.334
(2x1) + (3x1/10) + (3x1/100) + (4x1/1000)
two AND three hundred thirty-four thousandths
5,378,402
(5x1,000,000) + (3x100,000) + (7x10,000) + (8x1,000) +
(4x100) + (2x1)
five million three hundred seventy-eight thousand four
hundred-two
9,467.009
(9x1,000) + (4x100) + (6x10) + (7x1) + (9x1/1000)
nine thousand four hundred sixty-seven and nine thousandths
Try these independently:
407.71
3,207,413.5
0.456