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Finding the Fourth Proportional to 545.40, 818.20 and 220.80

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Solution

The fourth proportional to 545.40, 818.20 and 220.80 is: 331.24

Step by Step Solution

  1. Step 1: Write the proportion equation
    545.40 : 818.20 = 220.80 : x
  2. Step 2: Convert to fraction form
    545.40/818.20 = 220.80/x
  3. Step 3: Cross multiply
    545.40x = 818.20 × 220.80
  4. Step 4: Simplify right side
    545.40x = 180,658.56
  5. Step 5: Solve for x
    x = 180,658.56/545.40
  6. Step 6: Final answer
    x = 331.24

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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.