Solve area problem.
-A room measures $13 \mathrm{ft}$ by $21 \mathrm{ft}$. The ceiling is $12 \mathrm{ft}$ above the floor. the door is $3 \mathrm{ft}$ by $7 \mathrm{ft}$. A gallon of paint will cover $88.1 \mathrm{ft}^{2}$. How many gallons of paint are needed to paint the room (including the ceiling and not including the door). Round you answer up the the next whole number.
A) 3 gallons
B) 10 gallons
C) 22 gallons
D) 13 gallons

Question

Quizplus · Accepted Answer

The total area to be painted includes the ceiling and four walls, minus the door. The ceiling area is $13 \times 21 = 273 \mathrm{ft}^2$. Each pair of opposite walls has areas $13 \times 12 = 156 \mathrm{ft}^2$ and $21 \times 12 = 252 \mathrm{ft}^2$. Total wall area is $2 \times (156 + 252) = 816 \mathrm{ft}^2$. Subtract the door area: $816 - 21 = 795 \mathrm{ft}^2$. Total area to paint is $273 + 795 = 1068 \mathrm{ft}^2$. Dividing by the coverage per gallon: $1068 / 88.1 \approx 12.12$. Rounding up gives 13 gallons.

Solve Area Problem 13ft13 \mathrm{ft}13ft By 21ft21 \mathrm{ft}21ft the Ceiling Is 12ft12 \mathrm{ft}12ft

Solve Area Problem $13 \mathrm{ft}$ By $21 \mathrm{ft}$ the Ceiling Is $12 \mathrm{ft}$