Difference between revisions of "2012 AMC 8 Problems/Problem 21"

(See Also)
(Solution)
 
(3 intermediate revisions by 2 users not shown)
Line 1: Line 1:
 
==Problem==
 
==Problem==
Jenica has a large white cube that has an edge of 10 feet. She also has enough green paint to cover 300 square feet. Jenica uses all the paint to create a white square centered on each face, surrounded by a green border. What is the area of one of the white squares, in square feet?
+
Marla has a large white cube that has an edge of 10 feet. She also has enough green paint to cover 300 square feet. Marla uses all the paint to create a white square centered on each face, surrounded by a green border. What is the area of one of the white squares, in square feet?
 
<math> \textbf{(A)}\hspace{.05in}5\sqrt2\qquad\textbf{(B)}\hspace{.05in}10\qquad\textbf{(C)}\hspace{.05in}10\sqrt2\qquad\textbf{(D)}\hspace{.05in}50\qquad\textbf{(E)}\hspace{.05in}50\sqrt2 </math>
 
<math> \textbf{(A)}\hspace{.05in}5\sqrt2\qquad\textbf{(B)}\hspace{.05in}10\qquad\textbf{(C)}\hspace{.05in}10\sqrt2\qquad\textbf{(D)}\hspace{.05in}50\qquad\textbf{(E)}\hspace{.05in}50\sqrt2 </math>
  
 
==Solution==
 
==Solution==
If Jenica evenly distributes her <math>300</math> square feet of paint between the 6 faces, each face will get <math>300\div6 = 50</math> square feet of paint. The surface area of one of the faces of the cube is <math>10^2 = 100 </math> square feet. Therefore, there will be <math>100-50 = \boxed{\textbf{(D)}\ 50} </math> square feet of white on each side.
+
If Marla evenly distributes her <math>300</math> square feet of paint between the 6 faces, each face will get <math>300\div6 = 50</math> square feet of paint. The surface area of one of the faces of the cube is <math>10^2 = 100 </math> square feet. Therefore, there will be <math>100-50 = \boxed{\textbf{(D)}\ 50} </math> square feet of white on each side.
 +
 
 +
==Video Solution==
 +
https://youtu.be/LSmDtefPpps ~savannahsolver
  
 
==See Also ==
 
==See Also ==
 
{{AMC8 box|year=2012|num-b=20|num-a=22}}
 
{{AMC8 box|year=2012|num-b=20|num-a=22}}
 
{{MAA Notice}}
 
{{MAA Notice}}

Latest revision as of 11:11, 3 June 2023

Problem

Marla has a large white cube that has an edge of 10 feet. She also has enough green paint to cover 300 square feet. Marla uses all the paint to create a white square centered on each face, surrounded by a green border. What is the area of one of the white squares, in square feet? $\textbf{(A)}\hspace{.05in}5\sqrt2\qquad\textbf{(B)}\hspace{.05in}10\qquad\textbf{(C)}\hspace{.05in}10\sqrt2\qquad\textbf{(D)}\hspace{.05in}50\qquad\textbf{(E)}\hspace{.05in}50\sqrt2$

Solution

If Marla evenly distributes her $300$ square feet of paint between the 6 faces, each face will get $300\div6 = 50$ square feet of paint. The surface area of one of the faces of the cube is $10^2 = 100$ square feet. Therefore, there will be $100-50 = \boxed{\textbf{(D)}\ 50}$ square feet of white on each side.

Video Solution

https://youtu.be/LSmDtefPpps ~savannahsolver

See Also

2012 AMC 8 (ProblemsAnswer KeyResources)
Preceded by
Problem 20
Followed by
Problem 22
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25
All AJHSME/AMC 8 Problems and Solutions

The problems on this page are copyrighted by the Mathematical Association of America's American Mathematics Competitions. AMC logo.png