Students write, add and subtract numbers in scientific notation and understand what is meant by the term leading digit.
The key to scientific notation is realizing why it was created: So that we didn't have to write a LOT of zeros when trying to display a REALLY BIG number like 7,000,000,000,000 or a really small number like 0.0000000000352.
*Our key rule is to make sure we have only one number before the decimal point that is between 1 and 9.
Therefore: 567,000,000 = 5.67x 108
Remember: Every time you multiply by 10, you change the number by ONE place value.
In order for a number to be in scientific notated form, the number portion must be a number or decimal number 1 or more and less than 10.
A brief overview of the first page of the common core's lesson 9.
We have a rule that we need to follow when we want to add numbers that are in scientific notated form.
RULE: Be sure that exponents are the same.
We need exponents to be the same to add our base numbers together, and sometimes we need to increase or decrease place values of scientific notated numbers so that they are the same as the number we are adding.
Here is an example: (3.4 x 106) + (2.6 x 105)
We can not add these until the exponents are the same.
Sooooo...Let's change the larger exponent of 6 to a 5. This means that the number 3.4 increases it's size by one place value and becomes 34.
Now we have: (34 x 105) + (2.6 x 105)
Our answer will be 36.6 x 105 but WAIT...this isn't in scientific notated form!!
So we decrease the number 36.6 by one place value to become 3.66 and the exponent grows by one place value to become x 106.
Our final answer is 3.66 x 106
A brief overview of the first page of the common core's Lesson 9