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Finding the Fourth Proportional to 418.30, 627.45 and 406.78

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Solution

The fourth proportional to 418.30, 627.45 and 406.78 is: 610.17

Step by Step Solution

  1. Step 1: Write the proportion equation
    418.30 : 627.45 = 406.78 : x
  2. Step 2: Convert to fraction form
    418.30/627.45 = 406.78/x
  3. Step 3: Cross multiply
    418.30x = 627.45 × 406.78
  4. Step 4: Simplify right side
    418.30x = 255,234.11
  5. Step 5: Solve for x
    x = 255,234.11/418.30
  6. Step 6: Final answer
    x = 610.17

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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.