document.write( "Question 1179844: For this freqeuncy distribution find the: \r
\n" ); document.write( "\n" ); document.write( "A. Sample mean: (round to two decimal places)\r
\n" ); document.write( "\n" ); document.write( "B. Sample Standard Deviation (round to two decimal places)\r
\n" ); document.write( "\n" ); document.write( "X Frequency\r
\n" ); document.write( "\n" ); document.write( "1 3
\n" ); document.write( "2 7
\n" ); document.write( "4 10
\n" ); document.write( "6 8
\n" ); document.write( "7 4
\n" ); document.write( "

Algebra.Com's Answer #850165 by CPhill(1959)\"\" \"About 
You can put this solution on YOUR website!
Here's how to calculate the sample mean and sample standard deviation for the given frequency distribution:\r
\n" ); document.write( "\n" ); document.write( "**A. Sample Mean (x̄):**\r
\n" ); document.write( "\n" ); document.write( "1. **Calculate the sum of (x * frequency):**
\n" ); document.write( " * (1 * 3) + (2 * 7) + (4 * 10) + (6 * 8) + (7 * 4) = 3 + 14 + 40 + 48 + 28 = 133\r
\n" ); document.write( "\n" ); document.write( "2. **Calculate the total frequency (n):**
\n" ); document.write( " * 3 + 7 + 10 + 8 + 4 = 32\r
\n" ); document.write( "\n" ); document.write( "3. **Calculate the sample mean:**
\n" ); document.write( " * x̄ = (sum of (x * frequency)) / n
\n" ); document.write( " * x̄ = 133 / 32 ≈ 4.16\r
\n" ); document.write( "\n" ); document.write( "**B. Sample Standard Deviation (s):**\r
\n" ); document.write( "\n" ); document.write( "1. **Calculate (x - x̄)² for each x:**
\n" ); document.write( " * (1 - 4.16)² ≈ 9.99
\n" ); document.write( " * (2 - 4.16)² ≈ 4.67
\n" ); document.write( " * (4 - 4.16)² ≈ 0.03
\n" ); document.write( " * (6 - 4.16)² ≈ 3.39
\n" ); document.write( " * (7 - 4.16)² ≈ 8.07\r
\n" ); document.write( "\n" ); document.write( "2. **Multiply each (x - x̄)² by its frequency:**
\n" ); document.write( " * 9.99 * 3 ≈ 29.97
\n" ); document.write( " * 4.67 * 7 ≈ 32.69
\n" ); document.write( " * 0.03 * 10 ≈ 0.3
\n" ); document.write( " * 3.39 * 8 ≈ 27.12
\n" ); document.write( " * 8.07 * 4 ≈ 32.28\r
\n" ); document.write( "\n" ); document.write( "3. **Calculate the sum of the results from step 2:**
\n" ); document.write( " * 29.97 + 32.69 + 0.3 + 27.12 + 32.28 = 122.36\r
\n" ); document.write( "\n" ); document.write( "4. **Divide by (n - 1):**
\n" ); document.write( " * 122.36 / (32 - 1) = 122.36 / 31 ≈ 3.947\r
\n" ); document.write( "\n" ); document.write( "5. **Take the square root:**
\n" ); document.write( " * s = √3.947 ≈ 1.99\r
\n" ); document.write( "\n" ); document.write( "**Answers:**\r
\n" ); document.write( "\n" ); document.write( "A. Sample mean: 4.16
\n" ); document.write( "B. Sample standard deviation: 1.99
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