Rounding and Estimating Numbers

Rounding and estimating numbers has become common household word that is very much used, whether in sport, business, and health... in fact In everyday life, people are using math logic to derive at a solution. And in doing so, they are making a judgment call, also known as a simple estimation, or a “ ball park figure”. In order to understand how to do estimation, you must know the concepts behind rounding and estimating numbers. Therefore, estimation is a great tool that people use when making educated guesses in regard to a possible amount. For example, for argument let say the distance between New York and Boston is 600 miles, and in reality the real distance is about 640 miles. Yes it's Ok, because the estimation is close enough to the real for a quick idea.

Meanwhile in the business world,  the art of rounding numbers has become an excellent tool, because it renders things smooth and make number more manageable. But, before going any further in covering those two topics, let us pause and follow some basic rules.

When rounding off numbers, you must know the followings steps:

1) What number that am I rounding it to? Because, number can be rounding up and can also be rounding down.

2) Find the” place value” for the rounding of digit.

3) Look to the right of the digit you want to round off to.

4) If the number you are rounding is followed by 0, 1, 2, 3, 4, do not change the “rounding digit” but change all digits to the right of the rounding digit to ZERO

Example: 43 rounded to the nearest ten is 40.

Also remember that numbers can be rounded off to the nearest ten, the nearest hundred, the nearest thousand and so on.

5) If the number you are rounding is followed by 5, 6, 7, 8, or 9, round the number up, by adding one to the round off digit.

Example

Round 52,183 to the nearest hundred.

Solution

WE are rounding to the hundreds place which is the digit i. Since the digit to the right of the 1 is 8, add 1 to 1 to get 2. Change all digits to the right to zeros.

Hence, 52,183 rounded to nearest hundred is 52,200