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Finding the Fourth Proportional to 412.31, 618.32 and 138.39

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Solution

The fourth proportional to 412.31, 618.32 and 138.39 is: 207.54

Step by Step Solution

  1. Step 1: Write the proportion equation
    412.31 : 618.32 = 138.39 : x
  2. Step 2: Convert to fraction form
    412.31/618.32 = 138.39/x
  3. Step 3: Cross multiply
    412.31x = 618.32 × 138.39
  4. Step 4: Simplify right side
    412.31x = 85,568.61
  5. Step 5: Solve for x
    x = 85,568.61/412.31
  6. Step 6: Final answer
    x = 207.54

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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.