Explain the coding formula method and use a mean of the above example to find the average wage per worker.

Mathematics
Explain the coding formula method and use a mean of the above example to find the average wage per worker.

ScanSolve AI Answer

Answer

\text{}\146\text{}$

The coding formula method, also known as the assumed mean method or step-deviation method, simplifies the calculation of the mean, especially for grouped data or when data values are large. It involves shifting the origin and scaling the data to work with smaller, more manageable numbers.

Step 1: Explain the Coding Formula Method The formula for the mean (xˉ\bar{x}) using the coding method is: xˉ=A+fiuifi×c\bar{x} = A + \frac{\sum f_i u_i}{\sum f_i} \times c Where:

  • AA is the assumed mean, a value chosen from the data (often the midpoint of a central class interval).
  • fif_i is the frequency of each class.
  • uiu_i is the coded deviation for each class, calculated as ui=xiAcu_i = \frac{x_i - A}{c}.
  • xix_i is the midpoint of each class interval.
  • cc is the class width (or common factor) of the intervals.
  • fiui\sum f_i u_i is the sum of the products of frequencies and coded deviations.
  • fi\sum f_i is the total frequency (total number of observations).

Step 2: Create a Hypothetical Example Since the "above example" is not provided, let's create a hypothetical example for the wages of 40 workers to demonstrate the method. Assume the wages (in dollars) are grouped as follows:

Wages ($)Number of Workers (fif_i)
100-1205
120-14010
140-16015
160-1808
180-2002
Totalfi=40\sum f_i = 40

Step 3: Calculate Midpoints, Deviations, and Coded Deviations We choose an assumed mean (AA) and class width (cc). Let A=150A = 150 (midpoint of the class with the highest frequency) and c=20c = 20 (e.g., 120100120 - 100).

Wages ($)fif_iMidpoint (xix_i)di=xiAd_i = x_i - Aui=dicu_i = \frac{d_i}{c}fiuif_i u_i
100-1205110110150=40110 - 150 = -404020=2\frac{-40}{20} = -25×2=105 \times -2 = -10
120-14010130130150=20130 - 150 = -202020=1\frac{-20}{20} = -110×1=1010 \times -1 = -10
140-16015150150150=0150 - 150 = 0020=0\frac{0}{20} = 015×0=015 \times 0 = 0
160-1808170170150=20170 - 150 = 202020=1\frac{20}{20} = 18×1=88 \times 1 = 8
180-2002190190150=40190 - 150 = 404020=2\frac{40}{20} = 22×2=42 \times 2 = 4

Step 4: Sum the Frequencies and fiuif_i u_i From the table: fi=40\sum f_i = 40 fiui=1010+0+8+4=8\sum f_i u_i = -10 - 10 + 0 + 8 + 4 = -8

Step 5: Calculate the Mean Wage Substitute the values into the coding formula: xˉ=A+fiuifi×c\bar{x} = A + \frac{\sum f_i u_i}{\sum f_i} \times c xˉ=150+840×20\bar{x} = 150 + \frac{-8}{40} \times 20 xˉ=150+(0.2)×20\bar{x} = 150 + (-0.2) \times 20 xˉ=1504\bar{x} = 150 - 4 xˉ=146\bar{x} = 146

The average wage per worker is \boxed{\text{*}\146*}$

Was this helpful?

Still stuck on this one?

Ask a follow-up, and the answer starts from this question.

Got a different question?Ask your own question