1. **Problem statement:** A student must answer 10 out of 13 questions.
(i) He must answer at least the first two from the first 5 questions.
2. **Understanding the problem:**
- Total questions: 13
- Must answer: 10
- Condition: Must answer questions 1 and 2 (at least the first two from the first 5)
3. **Approach:**
- Since questions 1 and 2 must be answered, these 2 are fixed.
- Remaining questions to answer: $10 - 2 = 8$
- Remaining questions available: $13 - 2 = 11$
4. **Calculate the number of ways:**
- The student can choose any 8 questions from the remaining 11 questions.
- Number of ways is given by the combination formula:
$$\binom{n}{k} = \frac{n!}{k!(n-k)!}$$
- Here, $n=11$, $k=8$
5. **Calculate $\binom{11}{8}$:**
$$\binom{11}{8} = \binom{11}{3} = \frac{11 \times 10 \times 9}{3 \times 2 \times 1} = 165$$
6. **Final answer:**
- The student can answer the questions in **165** different ways under the given condition.
Question Selection 9Ee4Dc
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