Rounding

Learning Objectives Identify the place value of digits in whole numbers and decimals. Round whole numbers to any specified place value. Round decimal numbers to a specified place value (e.g., tenths, hundredths, thousandths). Apply the rules of rounding consistently and accurately. Use rounding to estimate answers in real-world contexts. Explain the purpose and utility of rounding for approximation. Have you ever seen a price like $9.99 or heard a weather report say 'about 25 degrees'? 🤔 These numbers are often the result of rounding! In this lesson, you'll discover the simple yet powerful rules for rounding both whole numbers and decimals. Mastering rounding will help you quickly estimate, simplify complex numbers, and make sense of quantities in everyday s...

TermDefinitionExample Place ValueThe position of a digit in a number that determines its value. For example, in 345, the '4' is in the tens place.In the number 1,234.56, the '2' is in the hundreds place, and the '5' is in the tenths place. RoundingThe process of approximating a number to a specified place value, making it simpler while keeping its value close to the original.Rounding 27 to the nearest ten gives 30, because 27 is closer to 30 than to 20. Rounding DigitThe digit in the place value to which you are rounding. This is the digit that will either stay the same or increase by one.When rounding 456 to the nearest ten, the '5' is the rounding digit. Look-to Digit (Decider Digit)The digit immediately to the right of the rounding digit. This di...

Identify the Rounding Digit Locate the place value to which you need to round. The digit in this position is your 'rounding digit'. This is the crucial first step to ensure you are rounding to the correct precision. Check the Look-to Digit Look at the digit immediately to the right of the rounding digit (the 'look-to digit'). This digit acts as your 'decider' to tell you whether to round up or down. Apply the Rounding Rule If the look-to digit is 5 or greater (5, 6, 7, 8, 9), increase the rounding digit by one. If the look-to digit is less than 5 (0, 1, 2, 3, 4), the rounding digit remains the same. This rule determines whether your number rounds up to the next value or stays at its current value. Adjust Trailing Digits For whole n...