approximate, approximation

• to estimate a number, amount or total, often
rounding it off to the nearest 10 or 100.

EXAMPLES:


Rounding Rules
more than 5 > up
less than 5 < down

~ for decimal fractions
1. Look at the digit in the place value to be rounded to.
2. Increase it by 1 if the digit to the right of it is 5 or more.
3. Leave it the same if the digit to the right of it is less than 5.
4. Remove everything to the right of the digit.
Example:
Round 625.475 to 1 decimal place ~ 625.475 ≈ 625.5
~ when rounding to 10 or above
there's an important change to step 4.
4. Replace whole numbers to the right of the digit with zero(s),
then remove everything to their right.
Examples:
Round 625.475 to 10 ~ 625.475 ≈ 630
Round 625.475 to 100 ~ 625.475 ≈ 600