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In this unit we went over Real Numbers and the classification system that is set up with Real Numbers. Here is the Rational Numbers Poster we created in class
We used Nesting boxes to demonstrate how the sub groups are inside each other.
Click here to do IDENTIFY REAL NUMBERS online and get automatic feedback (it grades it)! 🙂
Watch a video about ordering number here!
To order numbers there are a couple steps to follow.
1st: Convert all you numbers to decimals
2nd: Convert these to percents
3rd: Label a number line
4th: Put your numbers on the number line
Ascending versus Descending
To put numbers in order, place them from lowest (first) to highest (last).
This is called “Ascending Order”.
Example: Place 17, 5, 9 and 8 in ascending order.
- Answer: 5, 8, 9, 17
Sometimes you want the numbers to go the other way, from highest down to lowest, this is called “Descending Order”.
Example: Place 17, 5, 9 and 8 in descending order.
- Answer: 17, 9, 8, 5
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Scientific notation is about writing really big and really small numbers in an equivalent form.
We normally write numbers in what we call STANDARD NOTATION, but we can also write this number in SCIENTIFIC NOTATION.
For example the number three hundred and twenty.
SCIENTIFIC NOTATION: 3.2 × 102
When given a number in scientific notation you can easily convert the number to standard notation.
Convert from Scientific Notation: 3.6 × 1012
to Standard Notation
Now, since the exponent on 10 is positive, I know they are looking for a LARGE number, so I’ll need to move the decimal point in the positive direction (to the right), in order to make the number LARGER. Since the exponent on 10 is “12“, I’ll need to move the decimal point twelve places over.
First, I’ll move the decimal point twelve places over. I make little loops when I count off the places, to keep track:
Then I fill in the loops with zeroes:
In other words, the number is 3,600,000,000,000, or 3.6 trillion
Convert 4.2 × 10–7 to standard notation.
Since the exponent on 10 is negative, I am looking for a small number. Since the exponent is a seven, I will be moving the decimal point seven places. Since I need to move the point to get a small number, I’ll be moving it to the left. The answer is 0.00000042
Click here to do Scientific Notation practice online and get automatic feedback (it grades it)! 🙂