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Finding the Fourth Proportional to 618.62, 853.47 and 408.90

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Solution

The fourth proportional to 618.62, 853.47 and 408.90 is: 564.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    618.62 : 853.47 = 408.90 : x
  2. Step 2: Convert to fraction form
    618.62/853.47 = 408.90/x
  3. Step 3: Cross multiply
    618.62x = 853.47 × 408.90
  4. Step 4: Simplify right side
    618.62x = 348,983.88
  5. Step 5: Solve for x
    x = 348,983.88/618.62
  6. Step 6: Final answer
    x = 564.13

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.