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Statement -1 : Let A={x x is a prime num...

Statement -1 : Let `A={x` x is a prime numebr < 40 then number of different rational numbers whose numerator and denominator belong to A is 12.
because
Statement -2: `p/q` is a rational `Aq!=0` and `p,q epsilon I`

A

Statement -1 is True, Statement-2 is True, Statement -2 is a correct explanation for Statement -1

B

Statement -1 is True, Statement -2 is True, Statemetn -2 is NOT a correct explanation for Statement -1.

C

Statement -1 is True, Statement -2 is False.

D

Statement -1 is False, Statement -2 is True

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The correct Answer is:
To analyze the statements, we need to evaluate each statement step by step. ### Step 1: Identify the prime numbers less than 40 The prime numbers less than 40 are: - 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37 Counting these, we find there are a total of 12 prime numbers. **Hint**: Remember that prime numbers are those greater than 1 that have no divisors other than 1 and themselves. ### Step 2: Determine the number of different rational numbers A rational number can be expressed in the form \( \frac{p}{q} \), where \( p \) and \( q \) are integers, and \( q \neq 0 \). In this case, both \( p \) and \( q \) must be selected from the set of prime numbers \( A \). 1. **Choosing different primes for \( p \) and \( q \)**: - We can choose \( p \) and \( q \) from the 12 prime numbers. The number of ways to choose 2 different primes from 12 is given by the combination formula \( \binom{n}{r} \): \[ \binom{12}{2} = \frac{12 \times 11}{2 \times 1} = 66 \] - Each pair \( (p, q) \) can yield two distinct rational numbers: \( \frac{p}{q} \) and \( \frac{q}{p} \). So, the total number of different rational numbers from different primes is: \[ 66 \times 2 = 132 \] 2. **Choosing the same prime for \( p \) and \( q \)**: - If \( p = q \), then \( \frac{p}{q} = 1 \) for any prime \( p \). Since there are 12 primes, we have 12 additional rational numbers (one for each prime). ### Step 3: Total rational numbers Now, we add the two cases together: \[ 132 \text{ (from different primes)} + 12 \text{ (from same primes)} = 144 \] ### Conclusion - **Statement 1**: The statement claims that the number of different rational numbers is 12, which is incorrect. The correct number is 144. - **Statement 2**: This statement is true as it correctly defines the conditions for a rational number. ### Final Answer: - Statement 1 is **false**. - Statement 2 is **true**.
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