Probability English Hindi
1. **Problem Statement:** We are given that 30% of students offered English, 20% offered Hindi, and 10% offered both English and Hindi. We need to find the probability that a randomly selected student offered English or Hindi.
2. **Formula Used:** The probability of the union of two events $A$ and $B$ is given by:
$$P(A \cup B) = P(A) + P(B) - P(A \cap B)$$
where $P(A)$ is the probability of event $A$, $P(B)$ is the probability of event $B$, and $P(A \cap B)$ is the probability of both events occurring.
3. **Assigning Values:**
- Let $E$ be the event that a student offered English.
- Let $H$ be the event that a student offered Hindi.
Given:
$$P(E) = 0.30$$
$$P(H) = 0.20$$
$$P(E \cap H) = 0.10$$
4. **Calculate $P(E \cup H)$:**
$$P(E \cup H) = P(E) + P(H) - P(E \cap H) = 0.30 + 0.20 - 0.10 = 0.40$$
5. **Interpretation:** The probability that a randomly selected student offered English or Hindi is $0.40$, which as a fraction is $\frac{2}{5}$.
**Final Answer:**
$$\boxed{\frac{2}{5}}$$