The Joy of 9
Streaming video - 2007
Adding the digits of a multiple of 9 always gives a multiple of 9. For example: 9 x 4 = 36, and 3 + 6 = 9. Inmodular arithmetic, this property allows checking answers by "casting out nines." A related trick: mentally computing the day of the week for any date in history.
Saved in:
- Subjects
- Genres
- Educational films
- Published
-
[San Francisco, California, USA] :
The Great Courses
2007.
2017. - Language
- English
- Online Access
- A Kanopy streaming video
Cover Image - Item Description
- Title from title frames.
In Process Record.
Film - Physical Description
- 1 online resource (streaming video file) (32 minutes): digital, .flv file, sound
- Playing Time
- 00:31:55
- Format
- Mode of access: World Wide Web.
- Access
- AVAILABLE FOR USE ONLY BY IOWA CITY AND RESIDENTS OF THE CONTRACTING GOVERNMENTS OF JOHNSON COUNTY, UNIVERSITY HEIGHTS, HILLS, AND LONE TREE (IA).