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Rounding helps us to quickly estimate answers before working them out.

Always look at the digit to the right of the one you’re supposed to be rounding to.

• If the digit is between 0 and 4, you round down.
• If the digit is between 5 and 9, you round up.

For example, to round the number 1,121,565 to the nearest million, look at the digit in the hundred thousands column.

1 is less than 4, so it would be rounded down to 1,000,000.

Revise the value of rounding numbers to the nearest 10, 100 or 1000 with Albert and his jars of sweets in this animation!

To round a number to the nearest 10, look at the ones digit. If the ones digit is 5 or more, round up. If the ones digit is 4 or less, round down.

For example, 853 rounded to the nearest 10 would be 850 because 3 is in the ones column.

To round a number to the nearest 100, look at the tens digit. If the tens digit is 5 or more, round up. If the tens digit is 4 or less, round down.

For example, 853 rounded to the nearest 100 would be 900 because 5 is in the tens column.

To round a number to the nearest 1000, look at the hundreds digit. If the hundreds digit is 5 or more, round up. If the hundreds digit is 4 or less, round down.

For example, 853 rounded to the nearest 1000 would be 1000 because 8 is in the hundreds column.

How do you round 182,322 to the nearest ten thousand?

This number is in the hundred thousands.

8 is in the ten thousands column, meaning eighty thousand.

The nearest ten thousand could be 180,000 or 190,000.

To round to the nearest ten thousand look at the digit in the column to the right, the thousands.

2 is in the thousands column.

The rule is, if the number is between 0 and 4 round down.

Therefore, 182,322 rounded to the nearest ten thousand is 180,000.

The number line also shows that 182,322 is closer to 180,000. It is almost a quarter of the way to 190,000.

How do you round 182,322 to the nearest hundred thousand?

1 is in the hundred thousand column, meaning one hundred thousand.

The nearest one hundred thousand could be 100,000 or 200,000.

To round to the nearest hundred thousand, look at the digit in the column to the right, the ten thousands.

8 is in the the ten thousands column.

The rule is, if the number is 5 or more round up.

8 is larger than 5. Therefore, 182,322 will be rounded up to 200,000.

Plot the figures on a number line to check.

Question: Ali says that 4,562,145 rounded to the nearest million is 4,000,000. Why is she incorrect?

4 is in the million column, meaning four million.

The nearest million could be 4,000,000 or 5,000,000.

To round to the nearest million, look at the digit in the column to the right, the hundred thousands.

The number in the hundred thousands column is 5.

The rule is, if the number is 5 or more, round up.

Ali needed to round up to 5,000,000.