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Finding the Fourth Proportional to 545.15, 811.89 and 517.20

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Solution

The fourth proportional to 545.15, 811.89 and 517.20 is: 770.27

Step by Step Solution

  1. Step 1: Write the proportion equation
    545.15 : 811.89 = 517.20 : x
  2. Step 2: Convert to fraction form
    545.15/811.89 = 517.20/x
  3. Step 3: Cross multiply
    545.15x = 811.89 × 517.20
  4. Step 4: Simplify right side
    545.15x = 419,909.51
  5. Step 5: Solve for x
    x = 419,909.51/545.15
  6. Step 6: Final answer
    x = 770.27

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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.