Multiple choice

Seven points lie on a circle. How many chords can be drawn by joining these points.

  1. 22

  2. 21

  3. 23

  4. 24

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The number of chords that can be drawn by joining n points is given by the combination formula nC2. For 7 points, 7C2 = (7 * 6) / 2 = 21.

AI explanation

A chord is defined by a line segment connecting any two distinct points on the circle. To find the number of chords, we need to find the number of ways to choose 2 points out of the 7 given points. Using the combination formula nC2 = (n(n-1))/2, we calculate 7C2 = (7 * 6) / 2 = 21. Therefore, 21 chords can be drawn.