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The mean of the first n natural numbers ...

The mean of the first n natural numbers is 32, find n.

A

64

B

63

C

65

D

62

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AI Generated Solution

The correct Answer is:
To find the value of \( n \) when the mean of the first \( n \) natural numbers is 32, we can follow these steps: ### Step 1: Understand the formula for the mean The mean of a set of numbers is calculated as the sum of the numbers divided by the count of the numbers. For the first \( n \) natural numbers, the mean can be expressed as: \[ \text{Mean} = \frac{\text{Sum of first } n \text{ natural numbers}}{n} \] ### Step 2: Calculate the sum of the first \( n \) natural numbers The sum of the first \( n \) natural numbers is given by the formula: \[ \text{Sum} = \frac{n(n + 1)}{2} \] ### Step 3: Set up the equation for the mean According to the problem, the mean is 32. Therefore, we can set up the equation: \[ \frac{\frac{n(n + 1)}{2}}{n} = 32 \] ### Step 4: Simplify the equation By simplifying the left side, we get: \[ \frac{n(n + 1)}{2n} = \frac{n + 1}{2} \] So, the equation becomes: \[ \frac{n + 1}{2} = 32 \] ### Step 5: Cross-multiply to eliminate the fraction To eliminate the fraction, we can cross-multiply: \[ n + 1 = 2 \times 32 \] This simplifies to: \[ n + 1 = 64 \] ### Step 6: Solve for \( n \) Now, we can solve for \( n \) by isolating it: \[ n = 64 - 1 \] Thus, we find: \[ n = 63 \] ### Final Answer The value of \( n \) is \( 63 \). ---
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