Do Now
Evaluate each expression.
1. 123  1,000
123,000
2. 123  1,000
0.123
3. 0.003  100
0.3
4. 0.003  100
0.00003
Scientific notation is a method of writing
numbers that are very large or very small. A
number written in scientific notation has
two parts that are multiplied.
The first part is a number that is greater than or
equal to 1 and less than 10.
The second part is a power of 10.
Astronomy Application
Saturn has a diameter of about
Its distance from the Sun is about
1,427,000,000 km.
km.
Write Saturn’s diameter in standard form.
120000
120,000 km
Move the decimal point 5 places to
the right.
Astronomy Application
Saturn has a diameter of about
Its distance from the Sun is about
1,427,000,000 km.
km.
Write Saturn’s distance from the Sun in
scientific notation.
1,427,000,000
1,4 2 7,0 0 0,0 0 0
9 places
1.427 
9
10
km
The direction
When to move the decimal
to the right or the left.