TO FIRST PERSON TO ANSWER CORRECTLY

I think the answer is because the math adds up easily for this equation.

#TeamTrees

Hope this helps! <3

step-by-step explanation:

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