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Finding the Fourth Proportional to 387.98, 580.81 and 256.35

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Solution

The fourth proportional to 387.98, 580.81 and 256.35 is: 383.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    387.98 : 580.81 = 256.35 : x
  2. Step 2: Convert to fraction form
    387.98/580.81 = 256.35/x
  3. Step 3: Cross multiply
    387.98x = 580.81 × 256.35
  4. Step 4: Simplify right side
    387.98x = 148,890.00
  5. Step 5: Solve for x
    x = 148,890.00/387.98
  6. Step 6: Final answer
    x = 383.76

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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.