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Finding the Fourth Proportional to 618.70, 853.92 and 408.91

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Solution

The fourth proportional to 618.70, 853.92 and 408.91 is: 564.37

Step by Step Solution

  1. Step 1: Write the proportion equation
    618.70 : 853.92 = 408.91 : x
  2. Step 2: Convert to fraction form
    618.70/853.92 = 408.91/x
  3. Step 3: Cross multiply
    618.70x = 853.92 × 408.91
  4. Step 4: Simplify right side
    618.70x = 349,176.43
  5. Step 5: Solve for x
    x = 349,176.43/618.70
  6. Step 6: Final answer
    x = 564.37

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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.