It would probably be 675 cause i did it and got that
Answer:
8 X 10^(9)
Step-by-step explanation:
Originally we have 10 digit phone numbers excluding the area code.
For each face value we have these in store: 0,1,2,3,4,5,6,7,8,9 (total 10)
But if we exclude 1 and 0 for the first digit, we are left with 8 digits.
8P1 X .......
In a phone number, digits can repeat so we can choose out of these 10 numbers freely after this.
8P1 X 10P1 X 10P1 X...
Adding the area code while assuming 10P1 is just 10...we get:
1 X 1 X 1 X 8 X 10^(9)
= 8000000000
Very interesting question, thanks for the opportunity!
Answer:
y=-2x+5
Step-by-step explanation:
y=-2x+b
7=2+b
b=5
Therefore, y=-2x+5
X = first child
x +2 = 2nd child
x+ 4 = 3rd child
It doesn't matter if the ages are odd or even - there is two years between each child in age.
The sum would be
x + x + 2 + x + 4 or 3x + 6.
Lets try it with a sample age. Let's say the youngest is 5 middle is 7 and oldest is 9
The sum of their ages is 21 (5 + 7 + 9)
Using our answer of 3x + 6 where x is the age of the youngest child, we get
3(5) +6 which is also 21.
This could also be solved by having x represent the middle age child
x-2 is the youngest (2 years less than the middle)
x = the middle
x+2 is the oldest (2 years older than the middle)
The sum of these would be x-2 + x + x +2 or simply 3x (the 2's cancel out)
Since the middle child is 7 3x would mean 3 (7)=21
You could also set this up using x for the oldest child
x= oldest
x-2= middle
x-4= youngest (The sum of this is 3x - 6)
3 (9) -6 is also 21.