There are 200 individuals with a skin disorder, 120 had been exposed to the chemical `C_1`? 50 to chemical `C_2`, and 30 to both the chemicals `C_1`and `C_2`. Find the number of individuals exposed to(i) Chemical `C_1`but not chemical `C_2`

Explanation

To find the number of individuals exposed to chemical \( C_1 \) but not chemical \( C_2 \), we can use the principle of inclusion-exclusion. Let's break down the solution step by step.

### Step-by-Step Solution:

1. **Identify the Given Information**:
- Total individuals with skin disorder: \( |U| = 200 \)
- Individuals exposed to chemical \( C_1 \): \( |C_1| = 120 \)
- Individuals exposed to chemical \( C_2 \): \( |C_2| = 50 \)
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