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Finding the Fourth Proportional to 545.20, 814.80 and 428.24

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Solution

The fourth proportional to 545.20, 814.80 and 428.24 is: 640.00

Step by Step Solution

  1. Step 1: Write the proportion equation
    545.20 : 814.80 = 428.24 : x
  2. Step 2: Convert to fraction form
    545.20/814.80 = 428.24/x
  3. Step 3: Cross multiply
    545.20x = 814.80 × 428.24
  4. Step 4: Simplify right side
    545.20x = 348,929.95
  5. Step 5: Solve for x
    x = 348,929.95/545.20
  6. Step 6: Final answer
    x = 640.00

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.