Question: The river that Floyds Fork is a tributary of is how many miles long?
Context: The Feather River is the principal tributary of the Sacramento River, in the Sacramento Valley of Northern California.  The river's main stem is about 71 mi long.  Its length to its most distant headwater tributary is about 220 mi .  Its drainage basin is about 6000 sqmi .  The main stem Feather River begins in Lake Oroville, where its four long tributary forks join together—the South Fork, Middle Fork, North Fork, and West Branch Feather Rivers.  These and other tributaries drain part of the northern Sierra Nevada, and the extreme southern Cascades, as well as a small portion of the Sacramento Valley.  The river's drainage basin above Lake Oroville is 3222 sqmi , or about 53% of the whole. The Salt River is a 150 mi river in the U.S. state of Kentucky that drains 2920 sqmi .  It begins near Parksville, Kentucky, rising from the north slope of Persimmon Knob south of KY 300 between Alum Springs and Wilsonville, and ends at the Ohio River near West Point.  Taylorsville Lake is formed from the Salt River, and Guist Creek Lake is also in its drainage basin via Breshears Creek and Guist Creek. English Station is a neighborhood of Louisville, Kentucky centered along Shelbyville Road (US 60) and the Floyds Fork watershed. The North Fork Flathead River (Ktunaxa: "kqaskanmituk" ) is a 153 mi river flowing through British Columbia, Canada, south into the U.S. state of Montana.  It is one of the three primary forks of the Flathead River, the main inflow of Flathead Lake and a tributary of the Columbia River via the Clark Fork River and the Pend Oreille River.  The river is sometimes considered the upper headwaters of the Flathead River, although the North Fork is its official name in the U.S.  Other naming conventions for the river include Flathead River - North Fork, North Fork of Flathead River, and North Fork of the Flathead River. Fisherville is a neighborhood of Louisville, Kentucky, United States, which is centered along Taylorsville Road and Finchville Road.  It was originally named Curreys after Edward Currey, who opened a post office in 1833.  In 1847, it was renamed after Robert Fisher who had died two years earlier and operated a mill on Floyds Fork with his father, John.  The area became more commercial in the late 19th and early 20th centuries due to the opening of railroad tracks and the discovery of a mineral water well.  Visitors came for the therapeutic value of the mineral water, but when the well went dry in 1914 the area began its reversion to being a primarily residential area.  Fisherville is also home of one of Louisville's great Basketball coaches, Denny Crum, who coached for the University of Louisville for 30 years attaining 2 Men's Basketball Championships. City of Parks is a municipal project to create a continuous paved pedestrian and biking trail around the city of Louisville, Kentucky while also adding a large amount of park land.  The project was announced on February 22, 2005.  Current plans call for making approximately 4000 acre of the Floyds Fork floodplain in eastern Jefferson County into park space, expanding area in the Jefferson Memorial Forest, and adding riverfront land and wharfs along the Riverwalk Trail and Levee Trail.  There are also plans to connect the 100 mi Louisville trail to a planned seven mile (11 km) trail connecting the Southern Indiana cities of New Albany, Clarksville and Jeffersonville. Floyds Fork is a 62 mi tributary of the Salt River in Kentucky, directly south and east of Louisville.  It begins in Henry County, near Smithfield Kentucky flows through eastern Jefferson County and flows into the Salt River near Shepherdsville in Bullitt County. The Satsop River is a stream in the U.S. state of Washington.  It has three main tributary forks, the East Fork, West Fork, and Middle Fork Satsop Rivers.  The main stem Satsop River is formed by the confluence of the West and East Forks.  The Middle Fork is a tributary of the East Fork.  The three forks are much longer than the main stem Satsop itself, which flows south from the confluence only a few miles to join the Chehalis River near Satsop, Washington.  Other significant tributaries include the Canyon River and Little River, both tributaries of the West Fork Satsop, and Decker Creek, a tributary of the East Fork Satsop River.  The Satsop River's major tributaries originate in the Olympic Mountains and its southern foothills, the Satsop Hills, within Grays Harbor and Mason counties.  Most of the Satsop River's watershed consists of heavily wooded hill lands.  The upper tributaries extend into Olympic National Forest, approaching but not quite reaching Olympic National Park. The Jemez River is a tributary of the Rio Grande in the U.S. state of New Mexico.  The river is formed by the confluence of the East Fork Jemez River and San Antonio Creek, which drain a number of tributaries in the area of the Jemez Mountains and Santa Fe National Forest.  The Jemez River is about 50 mi long, or about 80 mi long if its longest headwater tributary, San Antonio Creek, is included.  The East Fork Jemez River is about 22 mi long.  Both San Antonio Creek and the East Fork Jemez River flow through intricate meanders along their courses.  The East Fork Jemez is a National Wild and Scenic River. The East Branch South Fork Eel River, a tributary of the South Fork Eel River, is formed by the confluence of Cruso Cabin Creek and Elkhorn Creek, in Mendocino County in the U.S. state of California.  The river is roughly 25 mi long, meandering west to its confluence with the South Fork Eel at Benbow Lake State Recreation Area.  Major tributaries of the East Branch include Buck Mountain Creek, Squaw Creek, Rays Creek, and Tom Long Creek.  The river flows west, turns north, and flows west again, through rugged terrain in the Coast Range of California.  The East Branch is the South Fork Eel's largest tributary.
Answer: 150