1. 1.4 Rounding and Order 1 Rounding off is the process of changing a number and expressing it to a certain accuracy. We will indicate accuracy by specifying a “given place value”. Accuracy indicates how exact we need to be in expressing a value. For example if you need to know the approximate income of your client last year and she made $42,882.46, you would probably answer “$43,000.” Your accuracy was “to the nearest thousand.” Accuracy Procedure: When asked to round off to a certain place value: 1. Underline the digit occupying that place value. 2. Look at the digit to its right. 3. If that digit is 5 or larger, add one to the place value digit. If that digit is less than 5, leave the place value digit alone (do not change). 4. Rewrite all the digits to the right of the place value digit as zeros. Rounding Off to a Given Place Value: Example 1. Round the following to the nearest ten. a) 68 b) 492 1. 68 2. Since the digit to the right is 5 or larger, add 1 to the tens place. Answer: 70 1. 492 2. Since the digit to the right is less than 5, leave the tens value digit alone. Answer: 490 Answer: a) 30 b) 860 Your Turn Problem #1 Round the following to the nearest ten. a) 34 b) 857

2. 1.4 Rounding and Order 2 Example 2. Round the following to the nearest hundred. a) 4,829 b) 7,951 1. 4,829 Answer: 4,800 2. Since the digit to the right is less than 5, leave the hundred digit alone. 2. Since the digit to the right is 5 or larger, add 1 to the hundreds. 1. 7,951 Answer: 8,000 (79+1 =80) Answer: a) 73,000 b) 408,300 Your Turn Problem #2 Round the following to the nearest hundred. a) 72,963 b) 408,257 Example 3. Round the following to the nearest thousand. a) 76,856 b) 39,476 1. 76,856 Answer: 77,000 2. Since the digit to the right is more than 5, add 1 to the thousands digit. 2. Since the digit to the right is less than 5, leave the thousands digit alone. 1. 39,476 Answer: 39,000 Answer: a) 45,000 b) 0 Your Turn Problem #3 Round the following to the nearest thousand. a) 45,378 b) 425

3. 1.4 Rounding and Order 3 1. 5,717,856 Answer: 6,000,000 2. Since the digit to the right is more than 5, add 1 to the millions digit. 2. Since the digit to the right is less than 5, leave the millions digit alone. 1. 83,476,455 Answer: 83,000,000 Your Turn Problem #4 Round the following to the nearest ten thousand. a) 245,211 b) 3,442,574 Example 4. Round the following to the nearest million. a) 5,717,364 b) 83,476,455 The process is the same for any place value, thousands, ten thousands, hundred thousands, millions, etc. Answer: a) 250,000 b) 3,440,00 The End B.R. 6-2-08