Please read the following table in Markdown format and then answer the question according to the table. Table cells in one row are seperated by '|', and different rows are seperated by '
'.

Table:
| No. in series | No. in season | Title | Directed by | Written by | Original air date | Production code | U.S. viewers (millions) |
| --- | --- | --- | --- | --- | --- | --- | --- |
| 29 | 1 | " Gay Witch Hunt " | Ken Kwapis | Greg Daniels | September21,2006 | 3001 | 9.11 |
| 30 | 2 | " The Convention " | Ken Whittingham | Gene Stupnitsky & Lee Eisenberg | September28,2006 | 3006 | 7.78 |
| 31 | 3 | " The Coup " | Greg Daniels | Paul Lieberstein | October5,2006 | 3002 | 8.89 |
| 32 | 4 | " Grief Counseling " | Roger Nygard | Jennifer Celotta | October12,2006 | 3003 | 8.83 |
| 33 | 5 | " Initiation " | Randall Einhorn | B. J. Novak | October19,2006 | 3005 | 8.46 |
| 34 | 6 | " Diwali " | Miguel Arteta | Mindy Kaling | November2,2006 | 3004 | 8.81 |
| 35 | 7 | " Branch Closing " | Tucker Gates | Michael Schur | November9,2006 | 3007 | 8.05 |
| 36 | 8 | " The Merger "† | Ken Whittingham | Brent Forrester | November16,2006 | 3008 | 8.63 |
| 37 | 9 | " The Convict " | Jeffrey Blitz | Ricky Gervais & Stephen Merchant | November30,2006 | 3010 | 9.07 |
| 38/39 | 10/11 | " A Benihana Christmas "‡ | Harold Ramis | Jennifer Celotta | December14,2006 | 3009/3014 | 8.44 |
| 40 | 12 | " Back from Vacation " | Julian Farino | Justin Spitzer | January4,2007 | 3011 | 8.80 |
| 41 | 13 | " Traveling Salesmen " | Greg Daniels | Michael Schur and Lee Eisenberg & Gene Stupnitsky | January11,2007 | 3012 | 10.12 |
| 42 | 14 | " The Return " | Greg Daniels | Lee Eisenberg & Gene Stupnitsky and Michael Schur | January18,2007 | 3013 | 10.2 |
| 43 | 15 | " Ben Franklin " | Randall Einhorn | Mindy Kaling | February1,2007 | 3015 | 10.11 |
| 44 | 16 | " Phyllis's Wedding " | Ken Whittingham | Caroline Williams | February8,2007 | 3016 | 8.84 |
| 45 | 17 | " Business School " | Joss Whedon | Brent Forrester | February15,2007 | 3017 | 8.84 |
| 46 | 18 | " Cocktails " | J. J. Abrams | Paul Lieberstein | February22,2007 | 3018 | 8.30 |
| 47 | 19 | " The Negotiation "† | Jeffrey Blitz | Michael Schur | April5,2007 | 3019 | 6.74 |
| 48 | 20 | " Safety Training " | Harold Ramis | B. J. Novak | April12,2007 | 3020 | 7.71 |
| 49 | 21 | " Product Recall " | Randall Einhorn | Justin Spitzer & Brent Forrester | April26,2007 | 3025 | 7.56 |
| 50 | 22 | " Women's Appreciation "† | Tucker Gates | Gene Stupnitsky & Lee Eisenberg | May3,2007 | 3021 | 7.00 |
| 51 | 23 | " Beach Games "† | Harold Ramis | Jennifer Celotta & Greg Daniels | May10,2007 | 3022 | 7.20 |
Question:
Name the number in the series for when the viewers is 7.78
Answer:
30.0