Using the fundamental counting theorem, we have that:
- 648 different area codes are possible with this rule.
- There are 6,480,000,000 possible 10-digit phone numbers.
- The amount of possible phone numbers is greater than 400,000,000, thus, there are enough possible phone numbers.
The fundamental counting principle states that if there are p ways to do a thing, and q ways to do another thing, and these two things are independent, there are ways to do both things.
For the area code:
- 8 options for the first digit.
- 9 options for the second and third.
Thus:

648 different area codes are possible with this rule.
For the number of 10-digit phone numbers:
- 7 digits, each with 10 options.
- 648 different area codes.
Then

There are 6,480,000,000 possible 10-digit phone numbers.
The amount of possible phone numbers is greater than 400,000,000, thus, there are enough possible phone numbers.
A similar problem is given at brainly.com/question/24067651
Answer:
61.66
Step-by-step explanation:
1. Multiply
2. divide
Answer:
First option: 6y^2sqrt(10) + 12sqrt(5y)
Step-by-step explanation:
3sqrt(10) * (2y^2 + 2sqrt(2y)
= 6y^2sqrt(10) + 6sqrt(20y)
= 6y^2sqrt(10) + 12sqrt(5y)
multipl 10×2=20 y ese es el resultado entendes ?
Answer:
undefined! one cannot divide by 0
Step-by-step explanation: