MathDB

14

Part of 2024 AMC 8 -

Problems(1)

Graph Theory?!?!??!?2.?!!>2r

Source: 2024 AMC 8 #14

10/11/2024
The one-way routes connecting towns AA, MM, CC, XX, YY, and ZZ are shown in the figure below (not drawn to scale).The distances in kilometers along each route are marked. Traveling along these routes, what is the shortest distance from A to Z in kilometers?
[asy] /* AMC8 P14 2024, by NUMANA: BUI VAN HIEU */ import graph; unitsize(2cm); real r=0.25; // Define the nodes and their positions pair[] nodes = { (0,0), (2,0), (1,1), (3,1), (4,0), (6,0) }; string[] labels = { "A", "M", "X", "Y", "C", "Z" };
// Draw the nodes as circles with labels for(int i = 0; i < nodes.length; ++i) { draw(circle(nodes, r)); label(""+labels+"" + labels + "", nodes); } // Define the edges with their node indices and labels int[][] edges = { {0, 1}, {0, 2}, {2, 1}, {2, 3}, {1, 3}, {1, 4}, {3, 4}, {4, 5}, {3, 5} }; string[] edgeLabels = { "8", "5", "2", "10", "6", "14", "5", "10", "17" }; pair[] edgeLabelsPos = { S, SE, SW, S, SE, S, SW, S, NE}; // Draw the edges with labels for (int i = 0; i < edges.length; ++i) { pair start = nodes[edges[0]]; pair end = nodes[edges[1]]; draw(start + r*dir(end-start) -- end-r*dir(end-start), Arrow); label(""+edgeLabels+"" + edgeLabels + "", midpoint(start -- end), edgeLabelsPos); } // Draw the curved edge with label draw(nodes[1]+r * dir(-45)..controls (3, -0.75) and (5, -0.75)..nodes[5]+r * dir(-135), Arrow); label("2525", midpoint(nodes[1]..controls (3, -0.75) and (5, -0.75)..nodes[5]), 2S); [/asy]
<spanclass=latexbold>(A)</span> 28<spanclass=latexbold>(B)</span> 29<spanclass=latexbold>(C)</span> 30<spanclass=latexbold>(D)</span> 31<spanclass=latexbold>(E)</span> 32<span class='latex-bold'>(A)</span>\ 28 \qquad <span class='latex-bold'>(B)</span>\ 29 \qquad <span class='latex-bold'>(C)</span>\ 30 \qquad <span class='latex-bold'>(D)</span>\ 31 \qquad <span class='latex-bold'>(E)</span>\ 32
2024 AMC 8AMC 8