Discrete Mathematics and Its Applications, Seventh Edition

Published by McGraw-Hill Education
ISBN 10: 0073383090
ISBN 13: 978-0-07338-309-5

Chapter 2 - Section 2.3 - Functions - Exercises - Page 154: 58

Answer

a)1 b) 2 c) 63 d) 375

Work Step by Step

(a) Given: n = 4 bits The number of bytes corresponding to n bits is then the number of bits divided by 8 (since a byte is a group of 8 bits) However the number of bytes always has to be an not an integer, thus if the result is not an integer, then we need to round the decimal up to the nearest integer (which corresponds to the ceiling function). $$\lceil{n/8}\rceil=\lceil{4/8}\rceil=\lceil{0.5}\rceil=1$$ (b) Given: n = 10 bits The number of bytes corresponding to n bits is then the number of bits divided by 8 (since a byte is a group of 8 bits) However the number of bytes always has to be an not an integer, thus if the result is not an integer, then we need to round the decimal up to the nearest integer (which corresponds to the ceiling function). $$\lceil{n/8}\rceil=\lceil{10/8}\rceil=\lceil{5/4}\rceil=\lceil{1.25}\rceil=2$$ (c) Given: n = 500 bits The number of bytes corresponding to n bits is then the number of bits divided by 8 (since a byte is a group of 8 bits) However the number of bytes always has to be an not an integer, thus if the result is not an integer, then we need to round the decimal up to the nearest integer (which corresponds to the ceiling function). $$\lceil{n/8}\rceil=\lceil{500/8}\rceil=\lceil{125/2}\rceil=\lceil{62.5}\rceil=63$$ (d) Given: n = 3000 bits The number of bytes corresponding to n bits is then the number of bits divided by 8 (since a byte is a group of 8 bits) However the number of bytes always has to be an not an integer, thus if the result is not an integer, then we need to round the decimal up to the nearest integer (which corresponds to the ceiling function). $$\lceil{n/8}\rceil=\lceil{3000/8}\rceil=\lceil{375}\rceil=375$$
Update this answer!

You can help us out by revising, improving and updating this answer.

Update this answer

After you claim an answer you’ll have 24 hours to send in a draft. An editor will review the submission and either publish your submission or provide feedback.