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Finding the Fourth Proportional to 580.20, 870.72 and 255.78

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Solution

The fourth proportional to 580.20, 870.72 and 255.78 is: 383.86

Step by Step Solution

  1. Step 1: Write the proportion equation
    580.20 : 870.72 = 255.78 : x
  2. Step 2: Convert to fraction form
    580.20/870.72 = 255.78/x
  3. Step 3: Cross multiply
    580.20x = 870.72 × 255.78
  4. Step 4: Simplify right side
    580.20x = 222,712.76
  5. Step 5: Solve for x
    x = 222,712.76/580.20
  6. Step 6: Final answer
    x = 383.86

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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.