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Finding the Fourth Proportional to 132.38, 183.78 and 128.42

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Solution

The fourth proportional to 132.38, 183.78 and 128.42 is: 178.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    132.38 : 183.78 = 128.42 : x
  2. Step 2: Convert to fraction form
    132.38/183.78 = 128.42/x
  3. Step 3: Cross multiply
    132.38x = 183.78 × 128.42
  4. Step 4: Simplify right side
    132.38x = 23,601.03
  5. Step 5: Solve for x
    x = 23,601.03/132.38
  6. Step 6: Final answer
    x = 178.28

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Why These Related Problems?

These problems maintain the same ratio (1.39) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.