Latest Dell Aptitude Question SOLUTION: which polygon has no. of sides = diagonal (Eg. Pentagon

• Placement Papers
• /
• Dell
• /
• Logical Reasoning
• /
• Cryptography

Dell Question Papers: DELL Company Profile

(#M40018397) DELL Logical Reasoning question Delloitte question Keep an EYE

which polygon has no. of sides = diagonal (Eg. Pentagon

Asked In Dell Amalesh Jana (11 years ago)

Unsolved Read Solution (12)

Is this Puzzle helpful?   (14)   (5) Submit Your Solution Cryptography

Read Solution (12) :

Vinay Sipani   (11 years ago)

nC2 - n = n
n(n-1)/2 = 2n
n^2 - 5n = 0

n = 0 or 5

Is this solution Helpfull? Yes (7) | No (1)  

Vinay Sipani   (11 years ago)

Circle is of infinite side and diagonal

Is this solution Helpfull? Yes (3) | No (3)  

Jasmine Khan  (11 years ago)

number of diagonals of a polygon having sides n is given by the formula,
number of diagonal=nC2-n
but we have given that number of sides are same as number of diagonals.
n=nC2-n
2n=n(n-1)/2
4n=n^2-n
0=n^2-5n
n-5=0
n=5
the polygon having 5 sides is pentagon.

Is this solution Helpfull? Yes (3) | No   

Aman  (11 years ago)

Pentagon with 5 sides and 5 diagonals.

Is this solution Helpfull? Yes (2) | No   

Susheelkumar Singh  (11 years ago)

Pentagon has 5 sides and 5 diagonals.

Is this solution Helpfull? Yes (2) | No   

bsrohit maurya  (11 years ago)

0 , 5
dont required any explanation

Is this solution Helpfull? Yes | No   

SANJEEV KUMAR SINGH  (11 years ago)

Number of diagonal in any polynomial=nC2-n
so if we take n=5,then 5C2-5 gives number of diagonal=5
Hence pentagon is the answer

Is this solution Helpfull? Yes | No   

Peddisetti Jahnavi  (10 years ago)

Pentagon
5 sides & 5 diagonals

Is this solution Helpfull? Yes | No   

Akash Taru Das  (10 years ago)

n=6

Let us have a polygon of n sides . To form a diagonal , it needs 2 points not adjacent to each other . Thus , number of diagonals possible of a n-sided polygon = (n-2)c(2)

Thus ,

2n=(n-2)(n-3)
n^2 - 7n + 6 = 0

Thus n=6 (a polygon can't be of only one side ).

Is this solution Helpfull? Yes | No   

Bharathi  (9 years ago)

n number of sides

Is this solution Helpfull? Yes | No   

shalu bansal  (9 years ago)

triangle triangle is having 3 sides and number of diagonal is also 3

Is this solution Helpfull? Yes | No   

anmol jain  (9 years ago)

pentagon (nc2-n)

Is this solution Helpfull? Yes | No   

Please Login to Read Solution.