Place Value/ Rounding Lesson #1

Reading and writing a decimal # 8.59 1122.0025

Standard Form The full number The way you “normally” write a number

What is the standard form of these expanded form numbers: 1) 800 + 40 + 3 = 2) 20 000 + 600 + 40 + 9 = 3) 1000x4 + 100x5 + 1x3 = 4) 100x9 + 1x8 + 1/10x5 =

Expanded Form Writing a number showing the total value of each digit Example: 543 100 x 5 = 500 10 x 4 = 40 1 x 3 = 3 So 543 = 500 + 40 + 3

Expanded Form: Practice Complete the expanded form of the following numbers: 1) 384 = _______ + 80 + _______ 2) 6257 = 6000 + ________ + ______ + ______ 3) 37 = 10x3 + ________ 4) 4826 = ________ + 100x8 + _______ + _____ 5) 219.2 = ______ + _______ + ______ + ______

Exponential form Place Value Number Exponential version Thousandth 0.001 Hundredth 0.01 Tenth 0.1 Ones 1 Tens 10 Hundreds 100 Thousands 1000 Ten Thousand 10 000 Hundred Thousand 100 000 Millions 1 000 000 Ten Millions 10 000 000

Exponential practice Write the following numbers in exponential form. 67.34 2 098 644

Rounding rules: Find the number in the place value you are asked to round to (ones, tens, hundredths) Look at the number to the right. If its 4 or less round down. If its 5 or more round up.

Examples Nearest tens: 1265 Nearest hundreds: 957 Nearest thousandths .3472 Nearest tenths .34