2
Given four different positions of a dice, determine the number opposite 3.
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Solution: Step 1: The goal is to find the number opposite 3.
Step 2: To find the opposite of 3, we can identify all numbers adjacent to it from the given figures.
Step 3: Examine Figure (i), where 2, 3, and 6 are visible. This indicates 2 and 6 are adjacent to 3.
Step 4: Examine Figure (iii), where 3, 1, and 5 are visible. This indicates 1 and 5 are adjacent to 3.
Step 5: Examine Figure (iv), where 3, 5, and 1 are visible. This confirms 1 and 5 are adjacent to 3.
Step 6: Combining these observations, the numbers 1, 2, 5, and 6 are all adjacent to 3.
Step 7: On a six-faced dice, if 1, 2, 5, 6 are adjacent to 3, then the only remaining number, 4, must be opposite to 3.
Step 8: Therefore, the number opposite 3 is 4.
4
Select all boxes that can be formed from the given paper sheet (X) by folding.
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Solution: Step 1: Recognize the given sheet (X) as a cube net, similar to Form II.
Step 2: Determine the pairs of opposite faces: The two half-shaded faces lie opposite each other. One of the three blank faces appears opposite to the face bearing a dot. The remaining two blank faces are opposite each other.
Step 3: Examine each cube option (1, 2, 3, 4).
Step 4: Verify that no option shows two half-shaded faces adjacent to each other.
Step 5: Verify that the dot face is never shown adjacent to the blank face it's opposite.
Step 6: Since all four cubes (1), (2), (3), and (4) demonstrate face arrangements consistent with the derived opposite pairs and can be achieved through valid rotations, all of them can be formed by folding sheet (X).
6
Two views of a die, numbered with 1 to 6 dots on its faces, are presented. If the die is currently resting on the face with three dots, what will be the number of dots on the face at the top?
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Solution: Step 1: Examine the provided figures (i) and (ii) and the solution's deduction.
Step 2: From figures (i) and (ii), the numbers 2, 4, and 6 are observed to be adjacent to 3 dots. (This implies these are the faces seen with 3 in some orientation, and 5 is not seen with 3).
Step 3: A standard die has numbers 1 through 6. If 2, 4, and 6 are adjacent to 3, then the remaining numbers are 1 and 5.
Step 4: One of these two remaining numbers (1 or 5) must be the fourth face adjacent to 3, and the other must be the face directly opposite to 3.
Step 5: Since there isn't enough information to definitively distinguish between 1 and 5 as the opposite face to 3, both are possibilities.
Step 6: If the die is resting on the side with three dots (meaning 3 is at the bottom), then the number of dots on the side at the top could be either 1 or 5.
8
From the provided dice positions, determine the number of dots on the face opposite the one with three dots.
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Solution: Step 1: The goal is to find the number of dots opposite 3 dots.
Step 2: To find the opposite of 3 dots, we can identify all faces adjacent to it from the given figures.
Step 3: Examine Figure (i), where 3, 6, and 4 dots are visible. This indicates 6 dots and 4 dots are adjacent to 3 dots.
Step 4: Examine Figure (ii), where 3, 1, and 2 dots are visible. This indicates 1 dot and 2 dots are adjacent to 3 dots.
Step 5: Examine Figure (iv), where 3, 4, and 1 dots are visible. This confirms 4 dots and 1 dot are adjacent to 3 dots.
Step 6: Combining these observations, the faces with 1, 2, 4, and 6 dots are all adjacent to the face with 3 dots.
Step 7: On a six-faced dice, if faces with 1, 2, 4, 6 dots are adjacent to the face with 3 dots, then the only remaining number of dots, 5, must be opposite to 3 dots.
Step 8: Therefore, there are 5 dots on the face opposite the one with three dots.
14
From the two provided positions of a single dice, numbered 1 through 6, determine the number opposite 3.
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Solution: Step 1: Observe the two given positions of the dice.
Step 2: Identify the visible faces in Figure (i): 5, 2, 6.
Step 3: Identify the visible faces in Figure (ii): 5, 1, 4.
Step 4: From Figure (i), the numbers adjacent to 5 are 2 and 6.
Step 5: From Figure (ii), the numbers adjacent to 5 are 1 and 4.
Step 6: Combining these observations, the numbers 1, 2, 4, and 6 are all adjacent to 5.
Step 7: A standard dice has 6 faces with numbers 1 through 6. If 1, 2, 4, 6 are adjacent to 5, then the only remaining number, 3, must be opposite to 5.
Step 8: Therefore, the number opposite 3 is 5.
15
How many small cubes will have red, green, and black colors on at least one face?
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Solution: Step 1: Understand that small cubes with three distinct colored faces (Red, Green, Black) are typically found at the corners of the original larger cuboid after it has been painted and cut.
Step 2: While the specific dimensions for this question are not explicitly given, the solution implies a configuration where 4 cubes meet this criterion.
Step 3: If the original cuboid is a 6x4x1 flat slab, it has 4 corners.
Step 4: Assuming a coloring scheme where these three distinct colors meet at these specific corner positions, then 4 such small cubes will be formed.
Step 5: Therefore, 4 cubes will have red, green, and black colors on at least one side.
16
The image displays four distinct positions of a die. Determine the number on the face directly opposite to the face showing 6.
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Solution: Step 1: Compare figures (i) and (iii). Both figures show the number '5' as a common face.
Step 2: In figure (i), moving clockwise from 5, the numbers are 4, then 3.
Step 3: In figure (iii), moving clockwise from 5, the numbers are 6, then 2.
Step 4: According to the common face rule, if a common face is in the same relative position (or if we trace clockwise), the numbers in corresponding positions are opposite to each other. Thus, 4 is opposite 6, and 3 is opposite 2.
Step 5: The remaining numbers are 1 and 5, so 1 is opposite 5.
Step 6: Based on this consistent set of opposite pairs ((1-5), (2-3), (4-6)), the number on the face opposite 6 is 4.
20
Given three distinct views (X, Y, and Z) of a single dice, determine the number that lies opposite 6.
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Solution: Step 1: Analyze positions X and Y.
Step 2: Identify the common number visible in both positions X and Y, which is '4'.
Step 3: Trace the visible faces in a clockwise direction starting from the common number.
Step 4: In Position X (from 4 clockwise): 4 -> 1 -> 5.
Step 5: In Position Y (from 4 clockwise): 4 -> 6 -> 3.
Step 6: By comparing these sequences, the numbers at corresponding positions are opposite to each other. Therefore, 1 is opposite 6, and 5 is opposite 3.
Step 7: The remaining number, 2, must be opposite the common face, 4.
Step 8: So, the complete set of opposite pairs is (1 vs 6), (5 vs 3), and (2 vs 4).
Step 9: The question asks for the number that lies opposite 6.
Step 10: From our established pairs, the number opposite 6 is 1.