EDEXCEL GCSE FOUNDATION MATHS - What is Rounding

Edexcel GCSE Foundation Maths: What is Rounding?

Rounding is a way of simplifying a number by making it easier to work with. We round numbers to a specific place value, such as the nearest ten, hundred, or thousand.

Understanding Place Value

Before we learn about rounding, it's important to understand place value. Each digit in a number has a specific value based on its position.

In the number 3,257:

• 3 is in the thousands place (worth 3000)
• 2 is in the hundreds place (worth 200)
• 5 is in the tens place (worth 50)
• 7 is in the units place (worth 7)

Rounding to the Nearest Ten

To round a number to the nearest ten, we look at the digit in the units place.

• If the units digit is 5 or more, we round the tens digit up by one.
• If the units digit is less than 5, we keep the tens digit the same.

Example:

• 37 rounded to the nearest ten is 40. (The units digit is 7, which is 5 or more, so we round the tens digit up.)
• 23 rounded to the nearest ten is 20. (The units digit is 3, which is less than 5, so we keep the tens digit the same.)

Rounding to the Nearest Hundred

To round a number to the nearest hundred, we look at the digit in the tens place.

• If the tens digit is 5 or more, we round the hundreds digit up by one.
• If the tens digit is less than 5, we keep the hundreds digit the same.

Example:

• 562 rounded to the nearest hundred is 600. (The tens digit is 6, which is 5 or more, so we round the hundreds digit up.)
• 128 rounded to the nearest hundred is 100. (The tens digit is 2, which is less than 5, so we keep the hundreds digit the same.)

Rounding to the Nearest Thousand

To round a number to the nearest thousand, we look at the digit in the hundreds place.

• If the hundreds digit is 5 or more, we round the thousands digit up by one.
• If the hundreds digit is less than 5, we keep the thousands digit the same.

Example:

• 2,754 rounded to the nearest thousand is 3,000. (The hundreds digit is 7, which is 5 or more, so we round the thousands digit up.)
• 1,329 rounded to the nearest thousand is 1,000. (The hundreds digit is 3, which is less than 5, so we keep the thousands digit the same.)

Summary

Rounding is a useful skill in everyday life and in mathematics. It helps us to estimate and simplify calculations. Remember to look at the digit to the right of the place value you are rounding to, and follow the rules to round up or down.