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Finding the Fourth Proportional to 545.21, 817.91 and 388.18

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Solution

The fourth proportional to 545.21, 817.91 and 388.18 is: 582.33

Step by Step Solution

  1. Step 1: Write the proportion equation
    545.21 : 817.91 = 388.18 : x
  2. Step 2: Convert to fraction form
    545.21/817.91 = 388.18/x
  3. Step 3: Cross multiply
    545.21x = 817.91 × 388.18
  4. Step 4: Simplify right side
    545.21x = 317,494.42
  5. Step 5: Solve for x
    x = 317,494.42/545.21
  6. Step 6: Final answer
    x = 582.33

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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.