September 21 2010 - Scientific Notation

First blog post! :) (other than the test post. That doesn't count)

Today, in class, we learned about Scientific Notation. We should have already learned this in grade 9 already, so this was more of a review.

Scientific notation is used to express very large or very small numbers using powers of 10.

For example, 25,100,000,000 would be expressed as 2.51x10^10, because for scientific notation, the number in the front has to be a number bigger than 1 and less than 10 (eg. 2.5, 6.7, 2.78). First, you move the decimal point (which is after the last digit [eg. 3487000 would be 3487000.0]) to the left until the number is between 0 and 10. Then, count the number of decimal places you moved over, and beside the new number, add a 10^# (10 to the power of #).

0.000000030 would be expressed as 3.02x10^-8. For negative equations, you move the decimal to the right instead of the left.




On the other hand, 3.25x10^8 would be expressed as 325,000,000, because you would move the decimal place over 8 spaces.



How to use Scientific Notation on a calculator:
1. Punch in the decimal number from 1-10
2. Press the 'EE' button
3. Punch in the power (10^17, press in 17, NOT 10^17)
4. Press ENTER :)

Alternate way (for dummies)
1. Punch in the decimal number from 1-10
2. Punch in 10
3. Punch in the (^) symbol
4. Punch in the power
5. Press enter :D

- Esther