Rounding off Decimal Fractions

Rounding off decimal fractions can also be rounded off to the nearest one to one place of decimal or to two places of decimals or as is required.

(i) 32.2 can be rounded off 32

(ii) 46.8 can be rounded off 47

(iii) 188.9 can be rounded off 189

(iv) 59.1 can be rounded off 59

(v) 170.2 can be rounded off 170

Sally bought a pair of shoes; the cost of a pair of shoes would probably read as $249.95. But she paid$ 250, i.e., $249.95 has been rounded off to$ 250.

Kelly bought a pair of shirts; the cost of a pair of shirts would probably read as $143.22. But she paid$ 143, i.e., $143.22 has been rounded off to$ 143.

Nearest 1

While rounding off a decimal fraction to the nearest one, if the digit in the tenths place is < 5 then the tenths place and the entire following place replace by 0. If the tenths place is equal to or > 5 then the digit in the ones place is increased by 1 and all digits after the decimal are reduced to 0.

Examples on rounding to the nearest ones:

(i) 49.37 → 49.00

We see the digit in the tenths place is 3 round to the nearest whole number which is smaller than the given decimal number. Since 3 < 5 then the decimal number is rounded to 49.00.

(ii) 96.872 → 97.00

If the digit in the tenths place is 8 round to the nearest whole number which is greater than the given decimal number. Since 8 > 5 then the decimal number is rounded to 97.00.

(iii) 67.437 → 67.000

We see the digit in the tenths place is 4 round to the nearest whole number which is smaller than the given decimal number. Since 4 < 5 then the decimal number is rounded to 67.000.

(iv) 9.909 → 10.000

If the digit in the tenths place is 9 round to the nearest whole number which is greater than the given decimal number. Since 9 > 5 then the decimal number is rounded to 10.000.

(v) 490.651 → 491.000

If the digit in the tenths place is 6 round to the nearest whole number which is greater than the given decimal number. Since 6 > 5 then the decimal number is rounded to 491.000.

(vi) 2492.201 → 2492.000

We see the digit in the tenths place is 2 round to the nearest whole number which is smaller than the given decimal number. Since 2 < 5 then the decimal number is rounded to 2492.000.

Note: Remember, to round off decimal numbers to the nearest ones (or units place), look at the digit in the tenths place.

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Round off to Nearest 10.

Round off to Nearest 100.

Round off to Nearest 1000.

Rounding off Decimal Fractions.

Correct to One Decimal Place.

Correct to Two Decimal Place.

Worksheet on Rounding off number.