Question 1116287
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 If the current of the river is 55 miles per ​hour, determine the speed of the boat in still
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{{{system((r-55)t=20,(r+55)t=40)}}}


{{{20/(r-55)=40/(r+55)}}}------simplify and solve this for r.


{{{1/(r-55)=2/(r+55)}}}



{{{2(r-55)=r+55}}}


{{{2r-110=r+55}}}


{{{r=165}}}