Round to the nearest ten
key notes:
Understanding Rounding
- Rounding means finding the nearest ten a number is closest to.
- It makes numbers simpler to work with.
Place Value Reminder
- Focus on the ones and tens place.
- The tens place tells us the groups of ten, and the ones place tells us the extra numbers.
Rounding Rules
Look at the ones digit:
- If it is 0, 1, 2, 3, or 4, round down (keep the tens place the same).
- If it is 5, 6, 7, 8, or 9, round up (increase the tens place by 1).
Examples
- 23 → 20 (since 3 is less than 5, round down)
- 37 → 40 (since 7 is 5 or more, round up)
- 45 → 50 (since 5 or more rounds up)
- 82 → 80 (since 2 is less than 5, round down)
Using a Number Line
- Find the two nearest tens (for 27, they are 20 and 30).
- See which ten the number is closer to.
Real-Life Applications
Estimating money and prices.
Rounding time (e.g., rounding 8:23 to 8:20).
Counting and estimating objects quickly.
Learn with an example
🎯 What is 26 rounded to the nearest ten?_____
- First, find the digit in the tens place. This is the place you want to round:
- 26
- Now look one place to the right:
- 26
- 6 is greater than 5, so you will round up. First, replace all the digits to the right of the tens place by zeroes:
- 26 → 20
- Now add 1 to the other part of the number:
- 20 → 30
🎯 What is 87 rounded to the nearest ten?_________
- First, find the digit in the tens place. This is the place you want to round:
- 87
- Now look one place to the right:
- 87
- 7 is greater than 5, so you will round up. First, replace all the digits to the right of the tens place by zeroes:
- 87 → 80
- Now add 1 to the other part of the number:
- 80 → 90
🎯 What is 23 rounded to the nearest ten?_____
- First, find the digit in the tens place. This is the place you want to round:
- 23
- Now look one place to the right:
- 23
- 3 is less than 5, so you will round down. Replace all the digits to the right of the tens place by zeroes:
- 23 → 20
Let’s practice!🖊️
