Thinking Mathematically (6th Edition)

Published by Pearson
ISBN 10: 0321867327
ISBN 13: 978-0-32186-732-2

Chapter 5 - Number Theory and the Real Number System - 5.1 Number Theory: Prime and Composite Numbers - Exercise Set 5.1 - Page 256: 72

Answer

d = 4

Work Step by Step

Divisibility Rules tell us that for a number to be divisible by 8, its last three digits must form a number that is divisible by 8. In our case: 8|88,888,82d. Our last three digits are 82d, with d being an unknown value we need to find. If we substitute each number 0 through 9 into 82d for d and check to see if the number formed is divisible by 8, we find that only 824 is divisible by 8. Therefore, d = 4.
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.