| 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 | 91%
|
| 19 | Baghdad | Shatt al-Arab | 89%
|
| 8 | Buenos Aires | Paranà | 79%
|
| 25 | Montreal | Saint Lawrence | 79%
|
| 18 | Nizhny Novgorod | Volga | 79%
|
| 6 | Jinan | Yellow | 79%
|
| 20 | Whitehorse | Yukon | 70%
|
| 7 | Novosibirsk | Ob | 66%
|
| 26 | Ciudad Juarez | Rio Grande | 64%
|
| 22 | Hyderabad | Indus | 60%
|
| 10 | Khabarovsk | Amur | 55%
|
| 11 | Yakutsk | Lena | 55%
|
| 14 | Port Harcourt | Niger | 51%
|
| 16 | Albury | Murray | 45%
|
| 13 | Inuvik | Mackenzie | 36%
|
| 5 | Krasnoyarsk | Yenisei | 36%
|
| 28 | Tete | Zambezi | 26%
|
| 23 | Tashkent | Syr Darya | 21%
|
| 24 | Mawlamyine | Salween | 11%
|
| 17 | Marabá | Tocantins | 9%
|
| 21 | Petrolina | São Francisco | 6%
|