How many possible combinations are there in a 3x3x3 rubics
cube?

In other words, if you wanted to solve the rubics cube by
trying different combinations, how many might it take you
(worst case senerio)?

How many for a 4x4x4 cube?



How many possible combinations are there in a 3x3x3 rubics cube? In other words, if you wanted ..

Answer / guest

There are 4.3252 * 10^19 possible combinations for 3x3x3
Rubics and 7.4012 * 10^45 possible combinations for 4x4x4
Rubics.

Let's consider 3x3x3 Rubics first.

There are 8 corner cubes, which can be arranged in 8! ways.

Each of these 8 cubes can be turned in 3 different
directions, so there are 3^8 orientations altogether. But if
you get all but one of the corner cube into chosen positions
and orientations, only one of 3 orientations of the final
corner cube is possible. Thus, total ways corner cubes can
be placed = (8!) * (3^8)/8 = (8!) * (3^7)

Similarly, 12 edge cubes can be arranged in 12! ways.

Each of these 12 cubes can be turned in 2 different
directions, so there are 2^12 orientations altogether. But
if you get all but one of the edge cube into chosen
positions and orientations, only one of 2 orientations of
the final edge cube is possible. Thus, total ways edge cubes
can be placed = (12!) * (2^12)/2 = (12!) * (2^11)

Here, we have essentially pulled the cubes apart and stuck
cubes back in place wherever we please. In reality, we can
only move cubes around by turning the faces of the cubes. It
turns out that you can't turn the faces in such a way as to
switch the positions of two cubes while returning all the
others to their original positions. Thus if you get all but
two cubes in place, there is only one attainable choice for
them (not 2!). Hence, we must divide by 2.

Total different possible combinations are

= [(8!) * (3^7)] * [(12!) * (2^11)] / 2

= (8!) * (3^7) * (12!) * (2^10)

= 4.3252 * 10^19

Similarly, for 4x4x4 Rubics total different possible
combinations are

= [(8!) * (3^7)] * [(24!)] * [(24!) / (4!^6)] / 24

= 7.4011968 * 10^45

Note that there are 24 edge cubes, which you can not turn in
2 orientations (hence no 2^24 / 2). Also, there are 4 center
cubes per face i.e. (24!) / (4!^6). You can switch 2 cubes
without affecting the rest of the combination as 4*4*4 has
even dimensions (hence no division by 2). But pattern on one
side is rotated in 4 directions over 6 faces, hence divide
by 24.

Is This Answer Correct ?    4 Yes 1 No

Post New Answer

More Puzzles Interview Questions

Pooja and Esha met each other after long time. In the course of their conversation, Pooja asked Esha her age. Esha replied, "If you reverse my age, you will get my husbund's age. He is of course older than me. Also, the difference between our age is 1/11th of the sum of our age." Can you help out Pooja in finding Esha's age?

1 Answers  


There are 3 persons X, Y and Z. On some day, X lent tractors to Y and Z as many as they had. After a month Y gave as many tractors to X and Z as many as they have. After a month Z did the same thing. At the end of this transaction each one of them had 24. Find the tractors each originally had?

1 Answers  


can anyone help me out in solving the following puzzle "i live in water,if you cut my head i am at your door,if you cut my tail i am a fuit,if you cut both,i am in you"

11 Answers   CTS, ESEC, TCS, Wipro,


Sarika multiplied 414 by certain number and obtained 69958 as the answer. But she found that there is some error in the answer - both the 9s in the answer are wrong and all the other digits are correct. Can you find the correct answer?

5 Answers   PayPal,


A woman took a certain number of eggs to the market and sold some of them. The next day, through the industry of her hens, the number left over had been doubled, and she sold the same number as the previous day. On the third day the new remainder was tripled, and she sold the same number as before. On the fourth day the remainder was quadrupled, and her sales the same as before. On the fifth day what had been left over were quintupled, yet she sold exactly the same as on all the previous occasions and so disposed of her entire stock. What is the smallest number of eggs she could have taken to market the first day, and how many did she sell daily? Note that the answer is not zero.

2 Answers   Athena Health Care,






A B C D E F G H I Each of the digits from 1 to 9 is represented by a different letter above. Also, A + B + C = C + D + E = E + F + G = G + H + I = 13 Which digit does E represent?

7 Answers  


2-3 ques on GDP growth rate ?

0 Answers   ONGC,


Plz mail me some aptitute questions which helps me to face SBI clerical exam.

3 Answers   Genpact, State Bank Of India SBI,


pleae send me previous five years SBI clerical questions to my mail(kristy.george@yahoo.com)

0 Answers   State Bank Of India SBI,


if (x-a) power(degree) is 1 and (x-a)(x-b) power is 2 then (x-a)(x-b).........upto ...(x-z) power(degree) is how much?

9 Answers   BA Continnum Solutions, HCL, Wipro,


Raj has a jewel chest containing Rings, Pins and Ear-rings. The chest contains 26 pieces. Raj has 2 1/2 times as many rings as pins, and the number of pairs of earrings is 4 less than the number of rings. How many earrings does Raj have?

5 Answers   Capital IQ,


can u prove that 1=2? is it possible?

17 Answers  


Categories