<span>Rounded numbers are easier to work with in your head. They are only approximate. An exact answer can not be obtained with these numbers. Sometimes an exact answer is not required.To round numbers to the nearest ten thousand, make the numbers whose last four digits are 0001 through 4999 into the next lower number that ends in 0000. For example 54,424 rounded to the nearest ten thousand would be 50,000. Numbers that have the last four digits of 5000 or more should be rounded up to the next even ten thousand. The number 78,988 rounded to the nearest ten thousand would be 80,000.this might help you understand
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The triangle has to equal to 180. So add them up and equal it to 180
Well, there are different ways to do this if you are really familiar with fractions, but "officially" :P
1) convert mixed numbers to improper fractions.
rule: a b/c = (ac+b)/c
2) make all fractions have a common denominator...
a/b+c/d
(a/b)(d/d)+(c/d)(b/b)
(ad/bd)+(cb/bd)
3)
The simplify your final answer with greatest common denominator or convert back to mixed number if needed...
Then mark it down by less then 1%, of by whatever the number would be.
X^2 + y^2 - x^2 +y^2
That would be (1x+1y)-(1x+1y)
