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Finding the Fourth Proportional to 140.39, 209.55 and 128.85

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Solution

The fourth proportional to 140.39, 209.55 and 128.85 is: 192.34

Step by Step Solution

  1. Step 1: Write the proportion equation
    140.39 : 209.55 = 128.85 : x
  2. Step 2: Convert to fraction form
    140.39/209.55 = 128.85/x
  3. Step 3: Cross multiply
    140.39x = 209.55 × 128.85
  4. Step 4: Simplify right side
    140.39x = 27,001.00
  5. Step 5: Solve for x
    x = 27,001.00/140.39
  6. Step 6: Final answer
    x = 192.34

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.