Carcass wrote:
Attachment:
The attachment cube.jpg is no longer available
The rectangular solid above is made up of eight cubes of the same size, each of which has exactly one face painted blue. What is the greatest fraction of the total surface area of the solid that could be blue?
A. \(\frac{1}{6}\)
B. \(\frac{3}{14}\)
C. \(\frac{1}{4}\)
D. \(\frac{2}{7}\)
E. \(\frac{1}{3}\)
Here,
As per the diagram,
The total area that can be blue = 8 sides in the front + 8 sides in the back + 4 sides in the top + 4 sides in the bottom + 2 sides in left side + 2 sides in the right side = 8 + 8 + 4 + 4 + 2 + 2 = 28 sides
So since the greatest no. of sides that can be painted = 8
Therefore the greatest fraction of the total surface area of the solid that could be blue = \(\frac{8}{28} = \frac{2}{7}\)
Attachments
Fig 3.jpg [ 16.98 KiB | Viewed 355 times ]
Fig 2.jpg [ 18.04 KiB | Viewed 354 times ]
Fig 1.jpg [ 21.41 KiB | Viewed 355 times ]
_________________
If you found this post useful, please let me know by pressing the Kudos Button
close
50% (01:03) correct
