An Ocean County couple pleaded guilty to a hit-and-run that left a juvenile bicyclist seriously injured, Prosecutor Bradley Billhimer said.Brittany Keifer was driving on Route 88 on Aug. 9, when she struck the girl and then fled, according to the plea.She then called Kyle Ramos, who picked her up several blocks away.The two hid the vehicle, and then tried to have it repaired to hinder the investigation, according to the charges.Keifer, 27, of Point Pleasant, turned herslef in the next day.She pleaded guilty Monday to leaving the scene of a motor vehicle accident resulting in serious bodily injury and leaving the scene of an accident.In exchange for her plea, she faces 364 days in the Ocean County Jail and probation.Ramos, 29, of Seaside Heights, pleaded guilty to hindering apprehension. The state will recommend probation.The two are set to be sentenced Feb. 7.