| Letter | # | Full List | Rivers | % Correct |
|---|---|---|---|---|
| M | 5 | Milk, Minnesota, Mississippi, Missouri, Musselshell | Missouri, Mississippi, Milk, ... | 98%
|
| C | 15 | Canadian, Cedar, Chattahoochee, Cheyenne, Cimarron, Clark Fork, Clinch, Colorado, Colorado, Columbia, Colville, Connecticut, Coosa, Copper, Cumberland | Colorado, Columbia, Canadian, ... | 96%
|
| R | 6 | Red (North), Red (South), Republican, Rio Grande, Roanoke, Rock | Rio Grande, Red (South), Red (North), ... | 91%
|
| O | 6 | Ocmulgee, Ogeechee, Ohio, Osage, Ouachita, Owyhee | Ohio, Ouachita, Ogeechee, ... | 88%
|
| A | 3 | Alabama, Allegheny, Arkansas | Arkansas, Allegheny, Alabama | 82%
|
| S | 22 | Sabine, Sacramento, Saline, Salmon, Salt, San Joaquin, San Juan, Savannah, Sevier, Sheyenne, Smoky Hill, Snake, Souris, South Fork Solomon, South Platte, St. Francis, St. John, St. Johns, St. Lawrence, Stikine, Susitna, Susquehanna | Snake, St. Lawrence, Sheyenne, ... | 82%
|
| P | 8 | Pearl, Pecos, Pembina, Pit, Platte, Porcupine, Potomac, Powder | Pecos, Porcupine, Pearl, ... | 74%
|
| H | 2 | Hudson, Humboldt | Humboldt, Hudson | 69%
|
| Y | 3 | Yampa, Yellowstone, Yukon | Yukon, Yellowstone, Yampa | 69%
|
| T | 6 | Tallapoosa, Tanana, Tennesee, Tensas, Tongue, Trinity | Trinity, Tennessee, Tanana, ... | 67%
|
| D | 4 | Delaware, Des Moines, Deschutes, Duck | Des Moines, Delaware, Duck, ... | 66%
|
| K | 7 | Kaskaskia, Kentucky, Klamath, Kobuk, Kootenai, Koyukuk, Kuskokwim | Kuskokwim, Kootenai, Koyukuk, ... | 59%
|
| G | 5 | Gasconade, Gila, Grand, Green, Green | Green, Gila, Green, ... | 57%
|
| I | 4 | Iditarod, Illinois, Innoko, Iowa | Innoko, Iditarod, Iowa, ... | 57%
|
| W | 8 | Wabash, Wapsipinicon, Washita, White, White, White, Wild Rice, Wisconsin | White, White, Wabash, ... | 53%
|
| N | 14 | Neches, Neosho, Neuse, New, Niobrara, Noatak, North Canadian, North Fork Kuskokwim, North Fork Red, North Fork Solomon, North Platte, Nowitna, Nueces, Nushagak | North Platte, Niobrara, Neosho, ... | 49%
|
| B | 10 | Bartholomew, Bear, Beaver, Belle Fourche, Big Black, Big Blue, Big Sioux, Bighorn, Black, Brazos | Brazos, Bighorn, Big Sioux, ... | 44%
|
| J | 3 | James, James, John Day | James, James, John Day | 24%
|
| L | 6 | Laramie, Licking, Little Colorado, Little Missouri, Little Sioux, Lodgepole | Little Missouri, Little Colorado, Licking, ... | 9%
|
| F | 1 | Flint | Flint | 4%
|
| E | 2 | Edisto, Elkhorn | Elkhorn, Edisto | 1%
|
| V | 1 | Verdigris | Verdigris | 1%
|