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If the mean of the following frequency d...

If the mean of the following frequency distribution is 8, find the value of p.
`{:("Variable"(x_(i)),3,5,7,9,11,13),("Frequency"(f_(i)),6,8,15,p,8,4):}`

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To find the value of \( p \) in the given frequency distribution, we will follow these steps: ### Step 1: Write down the given data We have the following values for the variable \( x \) and their corresponding frequencies \( f \): | \( x_i \) | 3 | 5 | 7 | 9 | 11 | 13 | |-----------|----|----|----|----|----|----| | \( f_i \) | 6 | 8 | 15 | \( p \) | 8 | 4 | ### Step 2: Calculate the total frequency \( \Sigma f \) The total frequency is the sum of all frequencies: \[ \Sigma f = 6 + 8 + 15 + p + 8 + 4 = 41 + p \] ### Step 3: Calculate \( \Sigma fx \) Next, we calculate \( \Sigma fx \) by multiplying each \( x_i \) by its corresponding \( f_i \): \[ \Sigma fx = (3 \times 6) + (5 \times 8) + (7 \times 15) + (9 \times p) + (11 \times 8) + (13 \times 4) \] Calculating each term: - \( 3 \times 6 = 18 \) - \( 5 \times 8 = 40 \) - \( 7 \times 15 = 105 \) - \( 9 \times p = 9p \) - \( 11 \times 8 = 88 \) - \( 13 \times 4 = 52 \) Now, summing these values: \[ \Sigma fx = 18 + 40 + 105 + 9p + 88 + 52 = 303 + 9p \] ### Step 4: Set up the equation for the mean The mean is given by the formula: \[ \text{Mean} = \frac{\Sigma fx}{\Sigma f} \] Given that the mean is 8, we can set up the equation: \[ 8 = \frac{303 + 9p}{41 + p} \] ### Step 5: Cross-multiply to eliminate the fraction Cross-multiplying gives us: \[ 8(41 + p) = 303 + 9p \] Expanding both sides: \[ 328 + 8p = 303 + 9p \] ### Step 6: Rearranging the equation Now, we will rearrange the equation to isolate \( p \): \[ 328 - 303 = 9p - 8p \] This simplifies to: \[ 25 = p \] ### Final Answer Thus, the value of \( p \) is \( 25 \). ---
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