Sign in
Please select an account to continue using cracku.in
↓ →
After a get-together every person present shakes the hand of every other person. If there were 105 hands shakes in all, how many persons were present in the party?
Total number of handshakes = 105, let number of persons be $$x$$
=> Number of handshakes =$$\left(x-1\right)+\left(x-2\right)+...+1=\frac{x(x-1)}{2}=105$$
=> $$x^2-x-210=0$$
=> $$(x-15)(x+14)=0$$
=> $$x=15,-14$$
$$\because -14$$ is not possible, hence number of persons = 15
=> Ans - (C)
Create a FREE account and get:
Book Free CAT Mentorship
Get personalized CAT strategy from a 99%iler
500+ students mentored
OTP Verification
Enter the 6-digit code sent to your phone
Booking Summary
Enter OTP
Didn't receive the OTP?
Educational materials for CAT preparation