q 28 please answer soon......
only answer if u know
Answers
Answer:
B) 8
Step-by-step explanation:
Consider one of the corners of the die in the middle.
There are 8 dice meeting at this corner, so there must be at least 8 different colours.
To show that 8 is the answer, we just need to show that it is possible to do it with as few as 8 colours.
Divide the cubes into sets as follows:
1 set of size 1: the middle die
3 sets of size 2: pairs of dice in the middle of opposite faces
3 sets of size 4: four edge dice in a plane that cuts the cube in half
1 set of size 8: the 8 corner dice
Notice this accounts for all 1×1 + 3×2 + 3×4 + 1×8 = 1+6+12+8 = 27 dice.
Also, no two dice in the same set meet at a corner, so the dice in a common set can safely be assigned the same colour.
The number of sets is 1 + 3 + 3 + 1 = 8.
So with 8 colours, we can assign a colour to each set and this achieves the required result.