Question

2- Let n a 4 be an integer. Take n distinct points on a circle and join each pair of points by a line segment. Colour the line segment joining every pair of adjacent points by blue and the rest by red. If the number of red and blue segments are equal, then the value of n is

Answer 1

Answer:

hue hue hue hue hue hue hue

Answer 2

Answer:

Number of red lines =nC2−n

Number of blue lines =n

Hence, nC2−n=n

nC2=2n

2n(n−1)=2n

n−1=4⇒n=5.