Copyright © 2012, 2009, 2005, 2002 Pearson Education, Inc. Chapter 3 Decimals

Copyright © 2012, 2009, 2005, 2002 Pearson Education, Inc. Comparing, Ordering, and Rounding Decimals 3.2

Copyright © 2012, 2009, 2005, 2002 Pearson Education, Inc. Comparing Decimals Comparing Two Numbers in Decimal Notation 1.Start at the left and compare corresponding digits. If the digits are the same, move one place to the right. 2.When two digits are different, the large number is the one with the larger digit. Since 4 < 5, we know that < The numbers in the tenths place are both 3. The numbers in the hundredths place are different.

Copyright © 2012, 2009, 2005, 2002 Pearson Education, Inc. Ordering Decimals Example: Place the following four decimals in order from smallest to largest Add zeros to make the comparison easier Rearrange with the smallest first , , 786.8,

Copyright © 2012, 2009, 2005, 2002 Pearson Education, Inc. Rounding Decimals 1.Find the decimal place (units, tenths, hundredths, and so on) for which rounding is required. 2.If the first digit to the right of the given place value is less than 5, drop it and all digits to the right of it. 3.If the first digit to the right of the given place value is 5 or greater, increase the number in the given place value by one. Drop all digits to the right of this place hundredths place Round the 4 up to hundredths place Do not round the 4 up.

Copyright © 2012, 2009, 2005, 2002 Pearson Education, Inc. Rounding Decimals Example: 1. Round to the nearest tenth Round to the nearest hundredth = 45.3