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

Explanation

To find the number of chords that can be drawn through 21 points on a circle, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Chords**: A chord is defined by two distinct points on the circumference of a circle. Therefore, to draw a chord, we need to select 2 points from the 21 points available.

2. **Choosing Points**: The number of ways to choose 2 points from 21 can be calculated using the combination formula:
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