Bigger bar charts and rounding · Usually met around P4
Rounding to tens and hundreds
Look at the next place: 0–4 down, 5–9 up.
How to do it
Method
Look at the next place: 0–4 down, 5–9 up
3456 → 5 tens → 3500
Another way
A number line
3456 is between 3400 and 3500, nearer 3500
In full
An approximation is a number close to the exact value. To round to the nearest ten, look at the ones: 0 to 4 round down (the tens stay), 5 to 9 round up (the tens go up 1), and the ones become 0: 347 → 350, 342 → 340. To the nearest hundred, look at the tens: 3456 has 5 tens, so round up to 3500. Or picture a number line: 3456 lies between 3400 and 3500, nearer 3500; exactly half-way (like 3450) rounds up. Careful: to the hundred, look only at the tens; don't round to the ten first.
Worked examples
Have a go first, then open each one for the answer and the working.
Example 1
6610 lies between the hundreds □ and □, and rounds to □ to the nearest hundred.
Fill in each box
Show the answer and working
Answer: 6600，6700，6600
6610 is between 6600 and 6700; the tens decide which is nearer: 6600.
Example 2
405 rounded to the nearest ten is 410.
True or false?
Show the answer and working
Answer: True
Look at the ones: 405 rounds to 410.
Example 3
A whole number rounds to 720 to the nearest ten. What is the largest it can be?
Show the answer and working
Answer: 724
Only ones of 0–4 round down to 720; a 5 would round up. The largest is 724.
Practise it in the game →Bigger bar charts and rounding · Free to start, unlimited questions, no download