Latest TCS Aptitude Question SOLUTION: if there are 31 persons shake hands with each other in cyclic sequence.then how many shakehands are possible?

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(#M40033737) TCS Numerical Ability question shakehand Keep an EYE

if there are 31 persons shake hands with each other in cyclic sequence.then how many shakehands are possible?

Asked In TCS swati sahebrao nat (10 years ago)

Solved RAKESH Read Solution (13)

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Read Solution (13) :

RAKESH  (10 years ago)

any person will shake hand with 31-1=30 persons & if two persons shake hand with each other it will counted 1

no. of shakehands = 31*(31-1)/2 = 31*15 = 465

Is this solution Helpfull? Yes (35) | No (24)  

ashish gandhi  (10 years ago)

since they are in cyclic sequence the ans will be n i.e 31

Is this solution Helpfull? Yes (34) | No (3)  

PAWAN  (10 years ago)

for the shake hand 2 persons is needed hence
from 31 person
no.of shake hands = 31c2=465

Is this solution Helpfull? Yes (14) | No (2)  

ajit jha  (10 years ago)

lets take example of four

a
b c
d

so in cycle of four
a shakes to b
b d
d c
c a

so 4 can shake 4 hands
this means in cycle of 31
31 hand shake is possible

Is this solution Helpfull? Yes (11) | No (1)  

poojitha  (10 years ago)

since, to shake hands we need 2 hands at a time. so it will be
31c2= 31*30*29!/29!*2
= 31*15
ans:465

Is this solution Helpfull? Yes (6) | No (3)  

pinki sharma  (10 years ago)

they are in cyclic sequence so answer should be 31....

Is this solution Helpfull? Yes (5) | No   

Rahul P R  (10 years ago)

as it is cyclic, i think, answer will be 31 only

Is this solution Helpfull? Yes (3) | No (1)  

abhishek kumar  (9 years ago)

As 31 persons sit in cyclic manner there would be only 31 hand shakes.465 hand shakes are possible when they shake hands randomly with anyone.
for ex: 4 persons A,B,C,D sitting in cyclic order can shake hands in this way
A-B,B-C,C-D,D-A.Similarly for 31 persons it would be 31 hand shakes only.

Is this solution Helpfull? Yes (3) | No   

D Sri Ram  (10 years ago)

The first person shakes his hand with 30 persons.
The second guy shakes his hand with 29 persons, excluding the 1st person and himself.
The third one shakes with 28.
So, the total number of shake hands are 30+29+28+....1
S= n/2(a+l),
where n=30, a=1, l=30
S= 465

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

Goldi kumari  (9 years ago)

n=31
using this formula
n(n-1)/2=31*(31-1)/2=31*30/2=465
ans:465

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

jitendra varshney  (9 years ago)

31c2=465 ans

Is this solution Helpfull? Yes (1) | No   

TANVI  (9 years ago)

since they are in cyclic sequence the ans will be n i.e 31 therefore 31c2 ans

Is this solution Helpfull? Yes | No (2)  

Vikash Anand  (9 years ago)

Total Shake hands=31c2=465

Is this solution Helpfull? Yes | No   

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