I think the answer is b. i'm not completely sure...
Split the room into 2 rectangles
area = 5*4 + 3*3 = 29 sq ft
So the cost is 29*8 = $232
We can convert grams to kilograms by dividing by 1000.
3500÷1000=3.5kg
Now we subtract this from her original weight
65.5-3.5= 62kg
$20 bought 16 songs
Therefore each song costs $20/16 = $5/4 = $1.25
So:
2 songs would cost 2 * $1.25
3 songs would cost 3 * $1.25
...
x songs would cost x * $1.25
Since Renata started with $20, then her balance (y) after buying x songs would be:
y = 20 - 1.25*x
