Discussion
If the number of faces and edges of a polyhedron is 5 and 8 respectively, then the number of its vertices is :
Answer: B
The polyhedron has 5 vertices.
Euler's formula for a polyhedron relates faces F, vertices V and edges E:
\[ \begin{aligned} F + V - E &= 2 \\ 5 + V - 8 &= 2 \\ V &= 5 \end{aligned} \]
A square pyramid fits these numbers: 5 faces (a square base and four triangles), 8 edges and 5 vertices. The option 8 repeats the number of edges. Neither 10 nor 15 satisfies the formula: 5 + 10 − 8 = 7 and 5 + 15 − 8 = 12, not 2.
No comment is present. Be the first to comment.
Loading…
Post your comment
Please log in or register to post a comment.
Examination Categories
- SSC Exams
- Banking Exams
- Teaching Exams
- Civil Services Exams
- Railways Exams
- Engineering Recruitment Exams
- Defence Exams
- State Government Exams
- Police Exams
- Insurance Exams
- Nursing Exams
- Other Government Exams
- NRA CET
- PG Entrance Exams
- Campus Placement
- MBA Entrance Exams
- CUET and UG Entrance
- Judiciary Exams
- Regulatory Body Exams
- Software Development