River c is 100 miles longer than river d. if the sum of their lengths is 5,500 miles, what is the length of river d?

it will cost dollar $540

the living room is 3 which means if we divide 325/3 then we get $108

therefore if 1part of the living room cost $108 and 3 costed $325

then total 5part of the room will cost 5*108 which gives $540