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Let E = [(1)/(3) + (1)/(50)]+[(1)/(3)+(2...

Let `E = [(1)/(3) + (1)/(50)]+[(1)/(3)+(2)/(50)]+[(1)/(3)+(3)/(50)]+……..` upto `50` terms where `[.]` denotes the greatest integer terms then

A

`E` is divisible by exactly `2` primes

B

`E` is prime

C

`E ge 30`

D

`E le 35`

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To solve the problem, we need to evaluate the expression \( E = \left[ \frac{1}{3} + \frac{1}{50} \right] + \left[ \frac{1}{3} + \frac{2}{50} \right] + \left[ \frac{1}{3} + \frac{3}{50} \right] + \ldots \) up to 50 terms, where \([.]\) denotes the greatest integer function. ### Step-by-step Solution: 1. **Understanding the Terms**: Each term in the series can be expressed as: \[ \left[ \frac{1}{3} + \frac{k}{50} \right] \quad \text{for } k = 1, 2, \ldots, 50 \] 2. **Finding the Value of Each Term**: We need to determine when the expression \( \frac{1}{3} + \frac{k}{50} \) is less than 1 and when it is greater than or equal to 1. - The critical point occurs when: \[ \frac{1}{3} + \frac{k}{50} < 1 \] Rearranging gives: \[ \frac{k}{50} < 1 - \frac{1}{3} = \frac{2}{3} \] Thus: \[ k < \frac{2}{3} \times 50 = \frac{100}{3} \approx 33.33 \] Therefore, \( k \) can take integer values from 1 to 33. 3. **Calculating the Greatest Integer Values**: For \( k = 1, 2, \ldots, 33 \): \[ \left[ \frac{1}{3} + \frac{k}{50} \right] = 0 \quad \text{(since it is less than 1)} \] Thus, the contribution to \( E \) from these terms is: \[ E_1 = 0 \text{ (from 33 terms)} \] 4. **Finding the Next Set of Terms**: For \( k = 34, 35, \ldots, 50 \): We check when: \[ \frac{1}{3} + \frac{k}{50} \geq 1 \] This occurs when: \[ \frac{k}{50} \geq \frac{2}{3} \quad \Rightarrow \quad k \geq \frac{100}{3} \approx 33.33 \] Thus, \( k \) can take values from 34 to 50 (17 terms). 5. **Calculating the Greatest Integer Values for Higher Terms**: For \( k = 34, 35, \ldots, 50 \): - The value of \( \frac{1}{3} + \frac{k}{50} \) will be in the range: \[ \frac{1}{3} + \frac{34}{50} \text{ to } \frac{1}{3} + \frac{50}{50} \] - The minimum value is: \[ \frac{1}{3} + \frac{34}{50} = \frac{1}{3} + 0.68 = 1.01 \quad \Rightarrow \quad \left[ 1.01 \right] = 1 \] - The maximum value is: \[ \frac{1}{3} + 1 = \frac{4}{3} \quad \Rightarrow \quad \left[ \frac{4}{3} \right] = 1 \] Therefore, for each of these 17 terms, we have: \[ \left[ \frac{1}{3} + \frac{k}{50} \right] = 1 \] 6. **Summing Contributions**: The total contribution from \( k = 34 \) to \( k = 50 \) is: \[ E_2 = 1 \times 17 = 17 \] 7. **Final Calculation**: Adding the contributions from both parts: \[ E = E_1 + E_2 = 0 + 17 = 17 \] ### Final Answer: \[ E = 17 \]

To solve the problem, we need to evaluate the expression \( E = \left[ \frac{1}{3} + \frac{1}{50} \right] + \left[ \frac{1}{3} + \frac{2}{50} \right] + \left[ \frac{1}{3} + \frac{3}{50} \right] + \ldots \) up to 50 terms, where \([.]\) denotes the greatest integer function. ### Step-by-step Solution: 1. **Understanding the Terms**: Each term in the series can be expressed as: \[ \left[ \frac{1}{3} + \frac{k}{50} \right] \quad \text{for } k = 1, 2, \ldots, 50 ...
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