How many chords can be drawn through 21 points on a circle?

Question

Accepted Answer

A chord is formed by joining any 2 points on a circle. The number of chords that can be drawn through 21 points is given by choosing 2 points out of 21, which is $^21C2 = \frac{21 	imes 20}{2 	imes 1} = 210$. Therefore, option D is correct.

Permutations and Combinations

❓ Sibling Questions in this Chapter