MUST SHOW WORK NEED HELP!1 ASAP

Work Shown:

x/21 = 12/15 ... see note below

15x = 21*12 ... cross multiply

15x = 252

x = 252/15 divide both sides by 15

x = 16.8

Note: x is opposite the double arc marking and 21 is opposite the single arc marking. Similarly, 12 is opposite the double arc and 15 is opposite the single arc. This order is important to set up the proportion.

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