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Finding the Fourth Proportional to 387.54, 581.18 and 285.48

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Solution

The fourth proportional to 387.54, 581.18 and 285.48 is: 428.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    387.54 : 581.18 = 285.48 : x
  2. Step 2: Convert to fraction form
    387.54/581.18 = 285.48/x
  3. Step 3: Cross multiply
    387.54x = 581.18 × 285.48
  4. Step 4: Simplify right side
    387.54x = 165,913.84
  5. Step 5: Solve for x
    x = 165,913.84/387.54
  6. Step 6: Final answer
    x = 428.12

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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.