1080p Netflix is 2-2.5 Mbps in practice because of video compression. You only get 1080p or better with certain browsers too. Many people use Netflix in Chrome or Firefox and only get 720p
3 GB / hour to Mbps = 6.667 Mb/s https://www.wolframalpha.com/input/?i=3+GB+%2F+hour+to+Mbps
7 GB / hour to Mbps = 15.56 Mb/s