Permutations And Combinations Question 371
Question: Let $ T _{n} $ denote the number of triangles which can be formed using the vertices of a regular polygon of n sides. If $ {T _{n+1}}-T _{n}=21 $ , then n equals
Options:
A) 5
B) 7
C) 6
D) 4
Correct Answer: B
Show Answer
Answer:
Solution:
BETA
