Internet videos have multiple versions of the same video, at different rates suppose $300$kbps$,1$Mbps$,$ and $3$Mbps$.$ Users watching the video over $3$G with a smartphone might choose the $300$kbps version.

Users can decide the download version they want to watch as a result of their current available bandwidth, keeping in in mind Higher is the bit rate, the better the image quality and the better the overall user viewing experience.

Explain with the help of numerical calculations why should this user use a $300$kbps$,$ not $1$ or $3$ Mbps video. $($Considering how $3$G networks have limited Bandwidth$)$