| Rank | Biggest City | Answer | % Correct |
|---|---|---|---|
| 2 | Cairo | Nile | 100%
|
| 1 | Manaus | Amazon | 98%
|
| 9 | Kinshasa | Congo | 98%
|
| 27 | Budapest | Danube | 96%
|
| 4 | Minneapolis | Mississippi | 96%
|
| 15 | Kolkata | Brahmaputra/Ganges | 94%
|
| 12 | Phnom Penh | Mekong | 94%
|
| 3 | Shanghai | Yangtze | 92%
|
| 19 | Baghdad | Shatt al-Arab | 88%
|
| 8 | Buenos Aires | Paranà | 79%
|
| 25 | Montreal | Saint Lawrence | 79%
|
| 18 | Nizhny Novgorod | Volga | 79%
|
| 6 | Jinan | Yellow | 79%
|
| 20 | Whitehorse | Yukon | 71%
|
| 7 | Novosibirsk | Ob | 67%
|
| 26 | Ciudad Juarez | Rio Grande | 65%
|
| 22 | Hyderabad | Indus | 60%
|
| 11 | Yakutsk | Lena | 56%
|
| 10 | Khabarovsk | Amur | 54%
|
| 14 | Port Harcourt | Niger | 52%
|
| 16 | Albury | Murray | 46%
|
| 5 | Krasnoyarsk | Yenisei | 38%
|
| 13 | Inuvik | Mackenzie | 35%
|
| 28 | Tete | Zambezi | 25%
|
| 23 | Tashkent | Syr Darya | 23%
|
| 24 | Mawlamyine | Salween | 10%
|
| 17 | Marabá | Tocantins | 8%
|
| 21 | Petrolina | São Francisco | 6%
|