Draw Lattice Diagram for K: Solving Algebra I Mapping Homework

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The discussion centers on solving a mapping homework problem involving a set K defined by specific conditions. The participant initially calculates 140 unique solutions but realizes that the professor does not expect all solutions to be drawn. They clarify that the conditions imply specific mappings for certain elements, reducing the complexity of the problem. Ultimately, they conclude that the remaining combinations can be simplified to a few distinct mappings. The participant resolves their confusion and indicates that they have found a solution.
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Homework Statement



K = {x C S7 | 2x=2, {1,4}x={1,4}, {1,5,7}x={1,5,7}}.
Draw Lattice Diagram for K.2. The attempt at a solution

I've looked at this for about 30 minutes and came to the conclusion that there are 140 unique solutions to this mapping, and I know for a fact that the professor does not want us to draw all 140 of these. Essentially, I found that 3!3!2!2! - 4 = 140. At this point I have no idea how to express this in a far easier form then what is given and I'm not sure where to go with the Lattice Diagram. Help would def be appreciated.
 
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Never mind. Mods can delete this thread because I've figured it out. The statement above states that {1,4}x = {1,4}, but similarly {1,5,7}x = {1,5,7}, which implies that for this statement to be true, 1 maps to 1, and 4 maps to 4, therefore all we are left with is combinations of {5,7} and {3,6}, which are simply (57)(36), I(36), (57)I, and I sub 7.
 
Question: A clock's minute hand has length 4 and its hour hand has length 3. What is the distance between the tips at the moment when it is increasing most rapidly?(Putnam Exam Question) Answer: Making assumption that both the hands moves at constant angular velocities, the answer is ## \sqrt{7} .## But don't you think this assumption is somewhat doubtful and wrong?

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