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Finding the Fourth Proportional to 579.78, 869.80 and 489.06

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Solution

The fourth proportional to 579.78, 869.80 and 489.06 is: 733.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    579.78 : 869.80 = 489.06 : x
  2. Step 2: Convert to fraction form
    579.78/869.80 = 489.06/x
  3. Step 3: Cross multiply
    579.78x = 869.80 × 489.06
  4. Step 4: Simplify right side
    579.78x = 425,384.39
  5. Step 5: Solve for x
    x = 425,384.39/579.78
  6. Step 6: Final answer
    x = 733.70

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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.