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Number and Algebra Estimating Often when we are doing calculations we can estimate the answer by rounding up a number to the nearest tens, hundreds etc.
Example: this can be rounded to = 30 so the approximate answer to is 30
When we give an answer that is approximate we use the symbol ≈ rather than = Hence ≈ 30
To round up a number we see which whole number it is closest to in terms of tens, hundreds etc. It will depend on the numbers in the question as to how you round up the number.
Example 932 could be rounded up to 930 or to 900, whereas 950 would be rounded to 1000 or left as 950
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