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Finding the Fourth Proportional to 528.30, 729 and 489.11

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Solution

The fourth proportional to 528.30, 729 and 489.11 is: 674.93

Step by Step Solution

  1. Step 1: Write the proportion equation
    528.30 : 729 = 489.11 : x
  2. Step 2: Convert to fraction form
    528.30/729 = 489.11/x
  3. Step 3: Cross multiply
    528.30x = 729 × 489.11
  4. Step 4: Simplify right side
    528.30x = 356,563.70
  5. Step 5: Solve for x
    x = 356,563.70/528.30
  6. Step 6: Final answer
    x = 674.93

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.