Estimating the area:
[tex]x = (20 \times 8)(13 \times 8) \\ x = 264[/tex]
Calculating wallpaper:
[tex]x = (264 \times 1.05) \div 35 \\ x = 7.92 \\ x = 8[/tex]
we round up here because they will need a full roll to complete the room. Since they can't buy 7.92 rolls, they must buy 8.
Calculating cost:
[tex]x = 8(31.48) + 31.48(0.0825) \\ x = 254.44[/tex]
