A box contains 20 red and 15 black balls. Two balls are drawn from the box one after the other without replacement. What is the probability that both drawn balls are red ?

Explanation

To find the probability that both drawn balls are red, we can follow these steps:

### Step 1: Determine the total number of balls
We have:
- 20 red balls
- 15 black balls

**Total number of balls = 20 + 15 = 35**
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