Three friends-whose walking rates are 1 ft./sec., 3ft./sec.,and 6ft./sec. start together walking in the same direction around a circular track that is 360 feet in circumference.After how many minutes are the three of them together again?	Select the correct option
A) 6 mins	B) 10 mins	C) 15 mins	D) 3 mins	E) 7 mins
The time they take will be what the 1st friend takes to complete one circumference as he is the slowest and that is the point all 3 of them will be together at the end of =360/60= 
<gadget id="calculator">360/60</gadget>
<output>6</output>
6 mins.   6 mins
<result>A</result>
Three friends-whose walking rates are 1 ft./sec., 3ft./sec.,and 6ft./sec. start together walking in the same direction around a circular track that is 360 feet in circumference.After how many minutes are the three of them together again?