| Length | River | % Correct |
|---|---|---|
| 2,202 mi | Mississippi | 100%
|
| (2,341 mi) | Missouri | 87%
|
| 1,450 mi | Colorado | 83%
|
| (979 mi) | Ohio | 68%
|
| 1,759 mi | Rio Grande | 68%
|
| (1,443 mi) | Arkansas | 42%
|
| 1,243 mi | Columbia | 40%
|
| (1,125 mi) | Red | 36%
|
| (1,040 mi) | Snake | 35%
|
| 1,979 mi | Yukon | 29%
|