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Finding the Fourth Proportional to 418.62, 628.14 and 388.20

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Solution

The fourth proportional to 418.62, 628.14 and 388.20 is: 582.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    418.62 : 628.14 = 388.20 : x
  2. Step 2: Convert to fraction form
    418.62/628.14 = 388.20/x
  3. Step 3: Cross multiply
    418.62x = 628.14 × 388.20
  4. Step 4: Simplify right side
    418.62x = 243,843.95
  5. Step 5: Solve for x
    x = 243,843.95/418.62
  6. Step 6: Final answer
    x = 582.49

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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.