<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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It’s the third one.. I think
First you need to know the definition of a complementary angle. That means that two angles add up to 90 degrees, or a right angle.
To find an angle complementary to a 78 degree angle, you need to subtract 78 from 90.
90 - 78 = 12
1 ft = 12 inches
(1 ft)^3 = (12 inches)^3
1 cubic foot = 1728 cubic inches
You'll multiply by the conversion factor (1278 in^3)/(1 ft^3) to convert from cubic feet to cubic inches. Notice how the cubic feet ft^3 unit is at the bottom of the conversion fraction, so that the cubic feet units cancel.
Answer: A) multiply by 1728
First Method:
Round 
to the closest integer, which is 1.
Round 
to the closest integer, which is also 1.
So 1 + 1 = 2.
Answer for method 1: 2
Second Method:
+ = 
is around 1
Answer for method 2: 1
The closest answer is 1.
