Solve the following using counting techniques. (a) The landline telephone numbers in the phone system in Islamabad city consist of seven digits, with the first digit not equal to zero. How many different numbers can be assigned in this system? (b) There are 12 signs of the zodiac. How many people are needed to guarantee that at least six of these people have the same sign? (c) How many bit strings of length 10 contain at least five Os?

Solve the following using counting techniques. (a) The landline telephone numbers in the phone system in Islamabad city consist of seven digits, with the first digit not equal to zero. How many different numbers can be assigned in this system? (b) There are 12 signs of the zodiac. How many people are needed to guarantee that at least six of these people have the same sign? (c) How many bit strings of length 10 contain at least five Os?

Elements Of Modern Algebra

8th Edition

ISBN:9781285463230

Author:Gilbert, Linda, Jimmie

Publisher:Gilbert, Linda, Jimmie

Chapter2: The Integers

Section2.8: Introduction To Cryptography (optional)

Problem 15E: a. Excluding the identity cipher, how many different translation ciphers are there using an alphabet...

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