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Finding the Fourth Proportional to 470.38, 705.61 and 128.38

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Solution

The fourth proportional to 470.38, 705.61 and 128.38 is: 192.58

Step by Step Solution

  1. Step 1: Write the proportion equation
    470.38 : 705.61 = 128.38 : x
  2. Step 2: Convert to fraction form
    470.38/705.61 = 128.38/x
  3. Step 3: Cross multiply
    470.38x = 705.61 × 128.38
  4. Step 4: Simplify right side
    470.38x = 90,582.68
  5. Step 5: Solve for x
    x = 90,582.68/470.38
  6. Step 6: Final answer
    x = 192.58

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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.