Answer:
The number of possible three-digit phone prefixes that are used to represent a particular geographic area is 640.
Step-by-step explanation:
The phone prefixes used to represent a particular geographic area are a 3 digit code consisting of numbers from 0 to 9.
The prefix code are of the form: <u>x</u> <u>x</u> <u>x</u>
Condition: The first or the second place cannot take values 0 or 1.
Then the first place can be occupied by the remaining 8 digits.
Similarly the second place can also be occupied by the remaining 8 digits.
And the third place can be occupied by any of the 10 digits.
So the number of ways to construct a phone prefix for any area is:

Thus, the number of phone prefixes possible for any area is 640.
Answer:
3/6x • 4/6x
12/6x
2x
Step-by-step explanation:
you would change both fractions to have the same denominator then simplify if needed
2.
0.05 miles
3.
a
4.
a
5.
1 Book for ever 10$
6.
28 MPH
Thats it!
Hope this helps
The answer is going to be 2*sqrt(5). You have to split it into perfect squares for it to be simplified... so in this case, I had sqrt(4*5) because sqrt(4) can be simplified... so your answer would be sqrt(4)*sqrt(5) or 2sqrt(5)