CAT Question Bank  Cubes and Cuboids

Q11) A cube has 7cm * 7cm * 7cm is kept in the corner of a room and painted in three different colours, each face in one colour. The cube cut into 343 smaller but identical cubes. How many smaller cubes have at the most two faces painted?

Q12) A cube has edge length 2. Suppose that we glue a cube of edge length 1 on top of the big cube so that one of its faces rests entirely on the top face of the larger cube. The percent increase in the surface area (sides, top, and bottom) from the original cube to the new solid formed is closest to:
a) 10
b) 15
c) 17
d) 21
e) 25

Q13) In how many different ways can a cube be painted if each face has to be painted either red or blue?

Q14) A cube has been cut into 150 smaller cubes of equal volume. What is the minimum number of straight cuts required to do this?

Q15) Two opposite faces of a cube are painted in blue, another pair of opposite faces are painted green and the remaining faces are painted in red. The cube is now cut into 210 smaller but identical pieces using minimum possible number of cuts. How many smaller pieces have exactly two colours on them?

Q16) A solid cube of side 1 cm is cut into two identical solid parts by a plane surface. The total surface area of both the solid parts is maximum possible. Two points are then selected on one of these solid parts. What is the maximum possible distance between these two points

Q17) What is the least possible number of cuts required to divide a cube into 34 identical pieces ?

Q18) A big cube is formed of 125 smaller cubes of which m are such that all their faces are coloured. If 60% of the area of the big cube is coloured, what is the maximum possible value of m

Q19) How many distinct cuboids can be formed using 64 cubes of area 1cm^2

Q20) A cube of dimension 4 cm × 4 cm × 4 cm is painted red on all six faces. Now this cube is cut to form 1 cm × 1 cm × 1 cm identical cubes. What is the ratio of total area of painted surfaces to the total area of unpainted surfaces

Q21) A cube is painted red and all its faces and is then divided into 343 equal cubes.
 How many cubes will have three faces painted ?
 How may cubes will have two faces painted?
 How many cubes will have one face painted?
 How many cubes have no face painted ?
 How many cubes will have at least one face painted?

Q22) A cuboid of size 5.2 m, 13 m & 39 m is completely cut into n smaller identical cubes. If n has the minimum possible value, what is the total surface area of all the small cubes?

Q23) The areas of three mutually adjacent faces of a cuboid C1 were found to be 200 sq. cm, 100 sq. cm and 50 sq. cm. Another cuboid C2 has the same volume as C1. Find the minimum value of the sum of the length, the breadth and the height of C2 (in cm).
a) 15
b) 30
c) 40
d) 50

Q24) There is a rectangular wooden block of length 4 cm, height 3 cm and breadth 3 cm. The two opposite surfaces of 4 cm x 3 cms are painted yellow on the outside. The other two opposite surfaces of 4 cm x 3 cm are painted red on the outside and the remaining two surfaces of 3 cm x 3 cm are painted green on the outside. Now, the block is cut in such a way that cubes of 1cm x 1cm x 1cm are created.
 How many cubes will have only one colour?
 How many cubes will have no colour?
 How many cubes will have any two colours?

Q25) A square has a perimeter of 108 cm. Four small squares are cut from each of its corners and the side of each square is x cm. The sheet remaining after the squares are cut is folded to form a cuboid. Find the value of x which maximizes the volume of the cuboid formed.

Q26) A set of 120 small 1 × 1 × 1 cubes are arranged to form a 6 × 5 × 4 cuboid. How many cuboids (including the original) can be formed with vertices chosen from these points such that their faces are parallel to those of the original cuboid?

Q27) How many right angle triangles can be obtained by joining the vertices of a cuboid?

Q28) A painted cuboid of dimensions 5 x 6 x 7 is cut into unit cubes. What is the number of unit cubes that have 0 faces painted?
a) 50
b) 60
c) 40
d) 210

Q29) If you have a 4 * 6 * 8 cuboid from which the largest possible cube is cut out, what would be the minimum number of cubes into which the remaining figure could be divided assuming that there is no piece left over and the all the smaller cubes are of equal dimension

Q30) A wooden cube of n unit on a side is painted red on all six faces and then cut into n^3 unit cubes. Exactly onefourth of the total number of faces of the unit cubes are red. What is n ?