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There are 50 numbers. Each number is sub...

There are 50 numbers. Each number is subtracted from 53 and the mean of the number so obtained is found to be `=3.5`. The mean of the given number is

A

46.5

B

49.5

C

53.5

D

56.5

Text Solution

AI Generated Solution

The correct Answer is:
To find the mean of the original 50 numbers, we can follow these steps: ### Step 1: Understand the given information We know that there are 50 numbers and each number is subtracted from 53. The mean of the resulting numbers is given as 3.5. ### Step 2: Set up the equation for the mean The mean of the numbers obtained after subtraction can be expressed as: \[ \text{Mean} = \frac{(53 - x_1) + (53 - x_2) + (53 - x_3) + \ldots + (53 - x_{50})}{50} \] This can be simplified to: \[ \text{Mean} = \frac{53 \times 50 - (x_1 + x_2 + x_3 + \ldots + x_{50})}{50} \] ### Step 3: Substitute the known mean We know that this mean equals 3.5, so we can set up the equation: \[ 3.5 = \frac{53 \times 50 - (x_1 + x_2 + x_3 + \ldots + x_{50})}{50} \] ### Step 4: Multiply both sides by 50 To eliminate the denominator, we multiply both sides by 50: \[ 3.5 \times 50 = 53 \times 50 - (x_1 + x_2 + x_3 + \ldots + x_{50}) \] Calculating the left side: \[ 175 = 2650 - (x_1 + x_2 + x_3 + \ldots + x_{50}) \] ### Step 5: Rearrange to find the sum of the original numbers Now, we can rearrange the equation to find the sum of the original numbers: \[ x_1 + x_2 + x_3 + \ldots + x_{50} = 2650 - 175 \] Calculating the right side gives: \[ x_1 + x_2 + x_3 + \ldots + x_{50} = 2475 \] ### Step 6: Calculate the mean of the original numbers The mean of the original numbers is given by: \[ \text{Mean} = \frac{x_1 + x_2 + x_3 + \ldots + x_{50}}{50} \] Substituting the sum we found: \[ \text{Mean} = \frac{2475}{50} \] Calculating this gives: \[ \text{Mean} = 49.5 \] ### Conclusion The mean of the given numbers is **49.5**. ---
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