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Finding the Fourth Proportional to 136.75, 204.65 and 128.85

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Solution

The fourth proportional to 136.75, 204.65 and 128.85 is: 192.83

Step by Step Solution

  1. Step 1: Write the proportion equation
    136.75 : 204.65 = 128.85 : x
  2. Step 2: Convert to fraction form
    136.75/204.65 = 128.85/x
  3. Step 3: Cross multiply
    136.75x = 204.65 × 128.85
  4. Step 4: Simplify right side
    136.75x = 26,369.15
  5. Step 5: Solve for x
    x = 26,369.15/136.75
  6. Step 6: Final answer
    x = 192.83

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.