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Finding the Fourth Proportional to 545.13, 818.13 and 285.21

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Solution

The fourth proportional to 545.13, 818.13 and 285.21 is: 428.04

Step by Step Solution

  1. Step 1: Write the proportion equation
    545.13 : 818.13 = 285.21 : x
  2. Step 2: Convert to fraction form
    545.13/818.13 = 285.21/x
  3. Step 3: Cross multiply
    545.13x = 818.13 × 285.21
  4. Step 4: Simplify right side
    545.13x = 233,338.86
  5. Step 5: Solve for x
    x = 233,338.86/545.13
  6. Step 6: Final answer
    x = 428.04

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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.