A MillionHow much is that???

Some examples of real-life ‘millions of things’??

94, 767, 083

• This is the number of copies of the Guinness Book of World Records sold from 1955 to 2002

• How do we know what this number is? How do we know how to read it?– – – –

Suppose we try to put that number into a chart:94, 767, 083

This is an example of a ‘place-value chart’

The following patterns help you understand large whole numbers:

- From right to left, each group of 3 place values in called a period.

- In each period, the digits of a number are read as hundreds(H), tens(T), and ones(O).

- Each position represents 10 times as many as the position to its right.

This place-value chart shows a record for the # of items in the world’s largest collection of matchbook covers –

3,159,119

We read this number as:Three million one hundred and fifty-nine thousand one hundred nineteen

We can write this number in three different forms:

• Standard form: 3 159 119** Notice we leave a space between the periods when we write

a number with 5 or more digits

• Expanded form: 3 000 000 + 100 000 + 50 000 + 9000 + 100 + 10 + 9

• Number-word form: 3 million 159 thousand 119

Any place value chart can be extended to the left to show greater whole numbers.

We write : 50 000 100 000 000We say: fifty trillion one hundred million

Practice Questions:

Handout

Number Forms:

• Standard Form – the actual number in digits only

• Expanded Form – the number as the sum of the values of its digits

• (e.g. 43 432 = 40 000 + 3000 + 400 + 30 + 2)• Number-Word Form– a combination of

number and words (e.g. 4 million, 546 thousand, 409)