#### Answer

Total number of 7's needed = 20

#### Work Step by Step

Number of 7's in each group of 10 from 1 to 99 = 10
Other than this, there will be 10 additional 7's from 70 to 79 .
10 + 10 = 20
therefore, total no of 7's required = 20

Published by
Pearson

ISBN 10:
0321867327

ISBN 13:
978-0-32186-732-2

Total number of 7's needed = 20

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

Update this answerAfter 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.