Example on discrete mathematics, Mathematics

Assignment Help:

Suppose that at some future time every telephone in the world is assigned a number that contains a country code, 1 to 3 digits long, that is, of the form X, XX , XXX or followed by a ten-digit telephone number of the form NXX-NXX-XXXX. A telephone number consists of ten digits, which are split into a three-digit area code, a three-digit office code, and a four-digit station code. Because of signaling considerations, there are certain restrictions on some of these digits.

To specify the allowable format, let denote a digit that can take any of the values 0 through 9 and let denote a digit that can take any of the values 2 through 9.

How many different telephone numbers would be available worldwide under this numbering plan?


Related Discussions:- Example on discrete mathematics

Trigonometry, A 25 foot ladder just reaches the top of a house and forms an...

A 25 foot ladder just reaches the top of a house and forms an angle of 41.5 degrees with the wall of the house. How tall is the house?

Theorem to computer the integral, Use green's theorem to computer the integ...

Use green's theorem to computer the integral F . dr where F = ( y^2 + x, y^2 + y) and c is bounded below the curve y= - cos(x),, above by y = sin(x) to the left by x=0 and to the r

Substitute 6 for r in the formula a = r^2 and solve for a, Find the area of...

Find the area of a circle along with a radius of 6 inches. The formula for the area of a circle is A = πr 2 . Use 3.14 for π. Substitute  6 for r in the formula A = πr 2 and solve

Compute projection scale factor, 1. A survey line on campus is measured to ...

1. A survey line on campus is measured to be 1000.00 ft long on horizontal ground. The elevation of the line is 700.00 feet and the geoid separation from ellipsoid to geoid is -110

What is addition rule of probability, Q. What is Addition Rule of probabili...

Q. What is Addition Rule of probability? Ans. Suppose there are 17 girls and 15 boys in your stats class. There are 17 + 15 = 32 ways for your teacher to pick one student

Sketch the direction field for the differential equation, Sketch the direct...

Sketch the direction field for the subsequent differential equation. Draw the set of integral curves for this differential equation. Find out how the solutions behave as t → ∞ and

Determine the function f ( x ) , Determine the function f ( x ) .       ...

Determine the function f ( x ) .             f ′ ( x )= 4x 3 - 9 + 2 sin x + 7e x , f (0) = 15 Solution The first step is to integrate to fine out the most general pos

Which of the following binomials could represent the length, The area of Mr...

The area of Mr. Smith's rectangular classroom is x 2 - 25. Which of the following binomials could represent the length and the width of the room? Since area of a rectangle is

Photogrammetry, basic linear algebra concepts and calculations in photogram...

basic linear algebra concepts and calculations in photogrammetry

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd