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Finding the Fourth Proportional to 387.60, 581.40 and 265.83

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Solution

The fourth proportional to 387.60, 581.40 and 265.83 is: 398.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    387.60 : 581.40 = 265.83 : x
  2. Step 2: Convert to fraction form
    387.60/581.40 = 265.83/x
  3. Step 3: Cross multiply
    387.60x = 581.40 × 265.83
  4. Step 4: Simplify right side
    387.60x = 154,553.56
  5. Step 5: Solve for x
    x = 154,553.56/387.60
  6. Step 6: Final answer
    x = 398.75

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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.