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Finding the Fourth Proportional to 387.09, 534.43 and 239.88

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Solution

The fourth proportional to 387.09, 534.43 and 239.88 is: 331.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    387.09 : 534.43 = 239.88 : x
  2. Step 2: Convert to fraction form
    387.09/534.43 = 239.88/x
  3. Step 3: Cross multiply
    387.09x = 534.43 × 239.88
  4. Step 4: Simplify right side
    387.09x = 128,195.80
  5. Step 5: Solve for x
    x = 128,195.80/387.09
  6. Step 6: Final answer
    x = 331.18

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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.