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

Decimal representations of some basic angles, Decimal representations of so...

Decimal representations of some basic angles: As a last quick topic let's note that it will, on occasion, be useful to remember the decimal representations of some basic angles. S

Solve the second order differential equations, Solve the subsequent IVP ...

Solve the subsequent IVP Y'' - 9 y = 0, y(0) = 2, y'(0) = -1 Solution First, the two functions  y (t ) = e 3t  and  y(t ) = e -3t That is "nice enough" for us to

Arc length with polar coordinates, Arc Length with Polar Coordinates H...

Arc Length with Polar Coordinates Here we need to move into the applications of integrals and how we do them in terms of polar coordinates.  In this part we will look at the a

Unit vector and zero vectors, Unit Vector and Zero Vectors Unit Vec...

Unit Vector and Zero Vectors Unit Vector Any vector along with magnitude of 1, that is || u → || = 1, is called a unit vector. Zero Vectors The vector w → = (

Calculate the volume and surface area of a cube, Calculate the volume and s...

Calculate the volume and surface area of a cube: Calculate the volume and surface area of a cube with a = 3".  Be sure to involved units in your answer. Solution: V =

Substitution rule, Substitution Rule ∫ f ( g ( x )) g′ ( x ) dx = ∫ f (...

Substitution Rule ∫ f ( g ( x )) g′ ( x ) dx = ∫ f (u ) du,     where, u = g ( x ) we can't do the following integrals through general rule. This looks considerably

Example of addition of fractions, Example of addition of Fractions: 10...

Example of addition of Fractions: 105/64 + 15/32 + 1/6 =____ would require the denominator to be equal to 64 x 32 x 6 = 12,288. This type of number is very hard to use.

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