Whole Numbers and Decimals Lesson 1.1

Place Value Chart

This chart can be broken into groups of three called “periods”

How to Read a Large Number Numbers are grouped in sets of three (each set is called a period). Only read three numbers at a time. Say the name of the place the third number is in. Say “and” for the decimal, but do not say “and” if there isn’t a decimal.

Example 4,658,089 The 4 is in the millions place, and it is the only digit in the millions period. 658 is in the thousands period (it ends in the thousands place) 089 is in the ones period. 089 is the same is 89, so we just say “eighty-nine.” Four million, six hundred fifty-eight thousand, eighty nine.

Example 2 625,409.36 625 is in the thousands period (the 5 is in the thousands place). 409 is in the ones period. Now we have a decimal! Say “and” at the decimal. Now, read the whole number after the decimal. 36 is read “thirty-six.” What place is the six in? That’s right, the hundredths place. Say “hundredths.” Six hundred twenty-five thousand, four hundred nine and thirty-six hundredths.

What is the value of the 4? There are two ways to answer questions like these. Write 4, followed by the place that the 4 is in. Write the value of 4, which you find by multiplying 4 times the place it’s in. 542 4 tens 40 (we get 40 by multiplying 4 times 10)

What is the value of the 7? 560.27 7 hundredths 0.07 OR

Standard Form Standard Form means: write it like a regular number. Four hundred sixty five million, nine hundred eleven thousand, twenty-six. REMEMBER: Numbers are grouped in periods, so only deal with three numbers at a time. The commas in the words become the commas in the number. 465,911,026 The ones period should always have three digits in it. Since twenty-six is only a two digit number, we make it 3 digits by writing 026.

13.25 Try another one Thirteen and twenty-five hundredths This one has “and” which means it has a ________ decimal. Write the number before “and.” Put a decimal where the “and” is. Now, look at the last word. How many spaces do you need? Fill in those spaces with the number twenty-five. 13.25

That’s It! You have done 2 examples of each type of problem. Now you’re ready to start the homework!