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 - 42
Expression Evaluated - 2 Times 17 Plus 8
We take the M and the N and substitute 17 for M and 8 for N, then we solve the problem.
Best Of Luck,
- Ari -
Answer:
A construction worker may use trigonometry when building the roof of a house. They may have to calculate the right angle that hypotenuse must sit at so water doesn't build up on the roof and cause leaks.
(this may be more of an architect's job, as they are the ones that design the houses)
or
An air traffic controller may use trigonometry to find how long it will take an airplane to land/how far the airplane is from the ground while it is in the sky (hypotenuse), based on its height from the ground (opposite) and the distance away from the runway it is (adjacent). They can also calculate the angle of elevation of the airplane from the tower they work in.
Answer:
18p? I don't know what other expressions could be equivalent. I just added 9p to 9p to get my answer.
A. 16 minutes.
b. around 3.5 tasks.