Large numbers, rounding and estimating
Read and build numbers in the millions in groups of three digits, round to the nearest 10, 100 or 1000 by looking at the next place, and estimate a sum before you work it out.
- UK: Year 3
- France: grade 4
- Germany: grade 2
- Iran: grade 2
- Afghanistan: grade 3
- Syria: grade 4
- Palestine: grade 3
- Ukraine: grade 4
- Russia: grade 4
Guide
We split big numbers into groups of three digits from the right: ones, thousands and millions. The name of each group is written above the chart, and in a written number a comma separates the groups: 2,050,300.
To read a number, read each group like a 3-digit number and then say the group's name: "two million, fifty thousand, three hundred". If a place is empty, the number shows a 0.
Places bigger than the thousands show counters instead of blocks. Each counter is worth its column's value.
To round (rounding) to the nearest hundred, find the nearest whole hundred. The place you round to is outlined, and the place to its right is dashed: look only at the dashed digit. 0 to 4: the outlined digit stays the same. 5 to 9: it goes up by one. Every place to the right becomes 0.
In Year 5 and 6 you round all the way to the nearest 1,000,000 in exactly the same way.
To estimate means to find an answer that is close, using rounded numbers, before working it out exactly. It tells you if your exact answer makes sense.