Rounding

Rounding is a process of approximating a number to a certain place value. It helps simplify numbers and make calculations easier. When we round a number, we determine which multiple of 10, 100, 1000, etc. the number is closest to.

Rounding to the Nearest Ten

To round a number to the nearest ten, look at the ones place. If the ones place is 5 or greater, round up; if it is less than 5, round down.For example:

Round 36 to the nearest ten: 36 is closer to 40 (4 tens) than 30 (3 tens), so 36 rounded to the nearest ten is 40.
Round 72 to the nearest ten: 72 is closer to 70 (7 tens) than 80 (8 tens), so 72 rounded to the nearest ten is 70.

Rounding to the Nearest Hundred

To round a number to the nearest hundred, look at the tens place. If the tens place is 5 or greater, round up; if it is less than 5, round down.For example:

Round 378 to the nearest hundred: 378 is closer to 400 (4 hundreds) than 300 (3 hundreds), so 378 rounded to the nearest hundred is 400.
Round 642 to the nearest hundred: 642 is closer to 600 (6 hundreds) than 700 (7 hundreds), so 642 rounded to the nearest hundred is 600.

Rounding to the Nearest Thousand

To round a number to the nearest thousand, look at the hundreds place. If the hundreds place is 5 or greater, round up; if it is less than 5, round down.For example:

Round 4,789 to the nearest thousand: 4,789 is closer to 5,000 (5 thousands) than 4,000 (4 thousands), so 4,789 rounded to the nearest thousand is 5,000.
Round 3,215 to the nearest thousand: 3,215 is closer to 3,000 (3 thousands) than 4,000 (4 thousands), so 3,215 rounded to the nearest thousand is 3,000.

Rounding Decimals

Rounding decimals follows similar principles to rounding whole numbers. Identify the place value to which you need to round and then look at the digit to the right of that place value. If it is 5 or greater, round up; if it is less than 5, round down.For example:

Round 3.67 to the nearest tenth: 3.67 is closer to 3.7 than 3.6, so 3.67 rounded to the nearest tenth is 3.7.
Round 8.234 to the nearest hundredth: 8.234 is closer to 8.23 than 8.24, so 8.234 rounded to the nearest hundredth is 8.23.

Study Guide for Rounding

To master the skill of rounding, it's important to practice rounding numbers to different place values. Here are some tips for effective studying:

Understand the concept of place value and how it relates to rounding.
Practice rounding both whole numbers and decimals to different place values.
Use number lines and visual aids to help you understand the concept of proximity and rounding up or down.
Work through plenty of practice problems to reinforce the rounding process.
Challenge yourself with word problems that involve rounding to apply the skill in real-life situations.