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Finding the Fourth Proportional to 387.29, 534.47 and 239.90

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Solution

The fourth proportional to 387.29, 534.47 and 239.90 is: 331.06

Step by Step Solution

  1. Step 1: Write the proportion equation
    387.29 : 534.47 = 239.90 : x
  2. Step 2: Convert to fraction form
    387.29/534.47 = 239.90/x
  3. Step 3: Cross multiply
    387.29x = 534.47 × 239.90
  4. Step 4: Simplify right side
    387.29x = 128,215.48
  5. Step 5: Solve for x
    x = 128,215.48/387.29
  6. Step 6: Final answer
    x = 331.06

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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.