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Finding the Fourth Proportional to 528.90, 729.89 and 307.86

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Solution

The fourth proportional to 528.90, 729.89 and 307.86 is: 424.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    528.90 : 729.89 = 307.86 : x
  2. Step 2: Convert to fraction form
    528.90/729.89 = 307.86/x
  3. Step 3: Cross multiply
    528.90x = 729.89 × 307.86
  4. Step 4: Simplify right side
    528.90x = 224,703.94
  5. Step 5: Solve for x
    x = 224,703.94/528.90
  6. Step 6: Final answer
    x = 424.85

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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.