Task: Question Answering
Input (English): Passage: In week 4, the Lions visited their divisional rival, the Minnesota Vikings. After a scoreless first quarter, the Lions got on the board with a 29-yard field goal by Matt Prater. The Vikings responded a few minutes later with a five-yard rushing touchdown by Dalvin Cook to make the score 7-3 in favor of Minnesota at half-time. The Lions scored 11 unanswered points in the second half. First, Prater kicked a 37-yard field goal to cut the Vikings' lead to three in the third quarter. Next, Detroit regained the lead with a three-yard rushing touchdown by Ameer Abdullah, followed by a two-point conversion pass from Matthew Stafford to T. J. Jones. Both third quarter scores followed Vikings fumbles that were recovered by the Lions. Detroit's Glover Quin forced another fumble by Adam Thielen with under two minutes left in the game, which was recovered by Tahir Whitehead to end Minnesota's attempt at a possible game-tying drive. 
Question: How many times did the Vikings fumble? 
Answer type: Number 
Output (English): 3.