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Finding the Fourth Proportional to 545.72, 819.30 and 429.80

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Solution

The fourth proportional to 545.72, 819.30 and 429.80 is: 645.27

Step by Step Solution

  1. Step 1: Write the proportion equation
    545.72 : 819.30 = 429.80 : x
  2. Step 2: Convert to fraction form
    545.72/819.30 = 429.80/x
  3. Step 3: Cross multiply
    545.72x = 819.30 × 429.80
  4. Step 4: Simplify right side
    545.72x = 352,135.14
  5. Step 5: Solve for x
    x = 352,135.14/545.72
  6. Step 6: Final answer
    x = 645.27

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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.