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Finding the Fourth Proportional to 387.21, 534.36 and 239.83

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Solution

The fourth proportional to 387.21, 534.36 and 239.83 is: 330.97

Step by Step Solution

  1. Step 1: Write the proportion equation
    387.21 : 534.36 = 239.83 : x
  2. Step 2: Convert to fraction form
    387.21/534.36 = 239.83/x
  3. Step 3: Cross multiply
    387.21x = 534.36 × 239.83
  4. Step 4: Simplify right side
    387.21x = 128,155.56
  5. Step 5: Solve for x
    x = 128,155.56/387.21
  6. Step 6: Final answer
    x = 330.97

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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.