Eddie, Rose, Jack and Mary are being chased by robbers to the riverside. Along the river, there was a boat that could only ferry $2$ people. Eddie takes $1$ minutes to row the boat across the river, Jack takes $2$ minutes, Rose takes $5$ minutes and Mary takes $10$ minutes. What is the shortest amount of time needed for all $4$ of them to cross the bridge?(There must be a person holding the flashlight to illuminate when crossing the bridge. 
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