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Finding the Fourth Proportional to 618.10, 851.31 and 499.87

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Solution

The fourth proportional to 618.10, 851.31 and 499.87 is: 688.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    618.10 : 851.31 = 499.87 : x
  2. Step 2: Convert to fraction form
    618.10/851.31 = 499.87/x
  3. Step 3: Cross multiply
    618.10x = 851.31 × 499.87
  4. Step 4: Simplify right side
    618.10x = 425,545.39
  5. Step 5: Solve for x
    x = 425,545.39/618.10
  6. Step 6: Final answer
    x = 688.48

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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.