10 questions · Form 4 Mathematics Bab 5: Network Theory
A subgraph G' = (V', E') of G = (V, E) must satisfy which conditions?
Prefer reading to quizzing? All 10 questions are listed below with the answer and explanation under each one.
1. A subgraph G' = (V', E') of G = (V, E) must satisfy which conditions?
Answer: A
By definition, a subgraph G' contains a subset of vertices V' ⊆ V and a subset of edges E' ⊆ E from the main graph G.
2. Which of the following is NOT a property of a tree in graph theory?
Answer: D
A tree must be connected and acyclic (contains no closed loops, cycles, or circuits).
3. In social network analysis represented by a graph, what do the vertices usually represent?
Answer: B
In social network graphs, vertices represent entities or individuals, while edges represent relationships or interactions.
4. Given set V = {1, 2, 3, 4} and set E = {(1, 2), (1, 3), (2, 3), (3, 4)}. What is the degree of vertex 3?
Answer: C
Vertex 3 appears in three edge pairs: (1, 3), (2, 3), and (3, 4). Therefore, its degree is 3.
5. In a directed graph, if a vertex has an in-degree of 3 and an out-degree of 2, what is its total degree?
Answer: B
Total degree of a vertex in a directed graph is the sum of its in-degree and out-degree: 3 + 2 = 5.
6. Which statement is true regarding the sum of in-degrees and out-degrees in a directed graph?
Answer: C
Every directed edge originates from one vertex (out-degree) and ends at another (in-degree). Thus, sum d_in(v) = sum d_out(v) = E.
7. If a graph has 4 vertices with degrees 1, 2, 3, and 2 respectively, how many edges does it contain?
Answer: A
Sum of degrees = 1 + 2 + 3 + 2 = 8. Using sum d(v) = 2E: 8 = 2E, so E = 4.
8. Given a simple graph with 5 vertices. What is the maximum possible number of edges it can have?
Answer: C
The maximum number of edges in a simple graph with n vertices is nn - 12. For n = 5, maximum edges = 542 = 10.
9. How many degree count contributions does a single loop at a vertex add to that vertex?
Answer: C
A loop connects a vertex to itself and both ends touch the vertex, adding 2 to the degree count of that vertex.
10. What is a weighted graph?
Answer: B
A weighted graph is a graph in which each edge is assigned a numerical weight representing quantities like cost, time, or distance.