It is that large number, 100,000,000,000 which causes the problem. Using one of the above examples, the number of stars in the Adromeda Galaxy can be written as: So, a system was developed to help represent these numbers in a way that was easy to read and understand: Scientific Notation. On the other hand, the weight of an alpha particle, which is emitted in the radioactive decay of Plutonium-239, is 0.000,000,000,000,000,000,000,000,006,645 kilograms.Īs you can see, it could get tedious writing out those numbers repeatedly. The Andromeda Galaxy (the closest one to our Milky Way galaxy) contains at least 200,000,000,000 stars. They are expressed in decimal form instead of scientific notation to help illustrate the problem: Here are two examples of large and small numbers. Scientific Notation was developed in order to easily represent numbers that are either very large or very small.

Be sure to check it out! Why Use Scientific Notation? Note: There are lots of numbers on this page that may be easier to read if the document is printed out.Ī ScientificNotationWorksheet+Answers>scientific notation worksheet accompanies this lesson. The reason you’ll study scientific notation is #prealgebra is because it’s a super convenient way to handle very large numbers, or very small numbers, including both positive and negative numbers.Įver wondered how to write the distance between earth and the sun as an actual number, when that number is so big? Or how to express the width of an atom as a number, when that number is so small? That’s the kind of thing we use scientific notation for! It gives us a quick, easy way to abbreviate something like 213,000,000,000,000,000,000,000,000, or write something like 0.0000000000000000000000000000184 in a better way.Why not just write “.000000000000000000001”? Why your wrist (or keyboard) will thank you for not writing all those zeros So the decimal number can’t be something like 0.13, because 0 is less than 1, and the decimal number can’t be something like 10.4, because 10 is greater than 9. Moreover, the number to the left of the decimal point must be between 1 and 9. There’s only format that qualifies as proper scientific notation, and that’s the product of a decimal term and a power of 10. Scientific notation is all about proper form.

How to do scientific notation