Difference between revisions of "2008 AMC 8 Problems/Problem 16"

(Created page with "==Problem 16== A shape is created by joining seven unit cubes, as shown. What is the ratio of the volume in cubic units to the surface area in square units? <asy> import three; ...")
 
m
 
(5 intermediate revisions by 5 users not shown)
Line 1: Line 1:
==Problem 16==
+
==Problem==
 
A shape is created by joining seven unit cubes, as shown. What is the ratio of the volume in cubic units to the surface area in square units?
 
A shape is created by joining seven unit cubes, as shown. What is the ratio of the volume in cubic units to the surface area in square units?
  
Line 16: Line 16:
  
 
<math>\textbf{(A)} \:1 : 6 \qquad\textbf{ (B)}\: 7 : 36 \qquad\textbf{(C)}\: 1 : 5 \qquad\textbf{(D)}\: 7 : 30\qquad\textbf{ (E)}\: 6 : 25</math>
 
<math>\textbf{(A)} \:1 : 6 \qquad\textbf{ (B)}\: 7 : 36 \qquad\textbf{(C)}\: 1 : 5 \qquad\textbf{(D)}\: 7 : 30\qquad\textbf{ (E)}\: 6 : 25</math>
 +
 +
==Solution==
 +
The volume is of seven unit cubes which is <math>7</math>. The surface area is the same for each of the protruding cubes which is <math>5\cdot 6=30</math>. The ratio of the volume to the surface area is <math>\boxed{\textbf{(D)}\: 7 : 30}</math>.
  
 
==See Also==
 
==See Also==
 
{{AMC8 box|year=2008|num-b=15|num-a=17}}
 
{{AMC8 box|year=2008|num-b=15|num-a=17}}
 +
{{MAA Notice}}

Latest revision as of 18:25, 8 August 2021

Problem

A shape is created by joining seven unit cubes, as shown. What is the ratio of the volume in cubic units to the surface area in square units?

[asy] import three; defaultpen(linewidth(0.8)); real r=0.5; currentprojection=orthographic(1,1/2,1/4); draw(unitcube, white, thick(), nolight); draw(shift(1,0,0)*unitcube, white, thick(), nolight); draw(shift(1,-1,0)*unitcube, white, thick(), nolight); draw(shift(1,0,-1)*unitcube, white, thick(), nolight); draw(shift(2,0,0)*unitcube, white, thick(), nolight); draw(shift(1,1,0)*unitcube, white, thick(), nolight); draw(shift(1,0,1)*unitcube, white, thick(), nolight);[/asy]

$\textbf{(A)} \:1 : 6 \qquad\textbf{ (B)}\: 7 : 36 \qquad\textbf{(C)}\: 1 : 5 \qquad\textbf{(D)}\: 7 : 30\qquad\textbf{ (E)}\: 6 : 25$

Solution

The volume is of seven unit cubes which is $7$. The surface area is the same for each of the protruding cubes which is $5\cdot 6=30$. The ratio of the volume to the surface area is $\boxed{\textbf{(D)}\: 7 : 30}$.

See Also

2008 AMC 8 (ProblemsAnswer KeyResources)
Preceded by
Problem 15
Followed by
Problem 17
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