UNDERSTANDING PLACE VALUE ROUNDING WHOLE NUMBERS

PLACE VALUE VS. FACE VALUE What is the difference between place value and face value? WRITE THIS DOWN Digits have face value, i.e. 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 Digits make numbers. Numbers have place value. With numbers we establish a decimal place. Why are they called Roman Numerals and not Roman Numbers?

ESTABLISHING PLACE VALUE MillionsHundred Thousands Ten Thousands HundredsTensOnes WRITE THIS DOWN Where does the decimal go for this number? How do we say this number? One million two hundred thirty four thousand five hundred seventy nine.

NUMBERS VS. DIGITS Tell me the number. Tell me the digit. One Million Two hundred Thousand Thirty Thousand Four Thousand Five Hundred Seventy One TwoThreeFour FiveSeven

ROUNDING WHOLE NUMBERS Here’s an example problem. Don’t worry about the answer. Since we are looking for the nearest hundred, the floor of 682 is 600 and the ceiling of 682 is 700. To determine which number is closest we must look at the digit in the following place, the tens place in this case. If the digit is greater than 5 then you rise, if it’s less than four then you floor.

ROUNDING WHOLE NUMBERS 700 First, we look at the number in the hundreds place. This means the number is between 600 and 700. Second, we look at the digit in the following place. Since this digit is greater than five, we rise. This makes the nearest hundred 700.

ROUNDING WHOLE NUMBERS 500 First, we look at the number in the hundreds place. This means the number is between 500 and 600. Second, we look at the digit in the following place. Since this digit is less than four, we floor. This makes the nearest hundred 500.

ROUNDING WHOLE NUMBERS How does the process change when we round to the nearest tens? What place determines if we rise or floor? What digit determines if we rise or floor? What is the floor of this number? 80 What is the ceiling of this number? 90 What is the nearest ten? 80

ROUNDING WHOLE NUMBERS What is the floor of this number? 530 What is the ceiling of this number? 540 What is the nearest ten? 540

ROUNDING WHOLE NUMBERS

EXIT TICKET Using ALEKS, send me a message with the subject “Rounding Whole Numbers Exit Ticket” In the body explain the process of rounding whole numbers, and the difference between rounding to the nearest ten, hundred and thousand. The quiz for this lesson is available in ALEKS under WHOLE NUMBERS – ROUNDING.