The bus traveled 55 + 10 = <<55+10=65>>65 miles going back to the starting point.
So, the bus traveled a total of 55 + 65 = <<55+65=120>>120 miles.
It took 120 x 2 = <<120*2=240>>240 minutes to travel.
Since there are 60 minutes in 1 hour, then the bus traveled for 240/60 = <<240/60=4>>4 hours.
Therefore, the entire tour took 4 + 2 = <<4+2=6>>6 hours.
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