In a committee, 50 people speak French, 20 speak Spanish and 10 speak both Spanish and French. How many speak at least one of these two languages?

Explanation

To solve the problem, we need to find the number of people who speak at least one of the two languages: French or Spanish. We can use the principle of inclusion-exclusion for this.

### Step-by-Step Solution:

1. **Identify the given values**:
- Let \( N_F \) be the number of people who speak French. \( N_F = 50 \)
- Let \( N_S \) be the number of people who speak Spanish. \( N_S = 20 \)
- Let \( N_{F \cap S} \) be the number of people who speak both languages. \( N_{F \cap S} = 10 \)
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