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Finding the Fourth Proportional to 388.40, 535.92 and 239.12

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Solution

The fourth proportional to 388.40, 535.92 and 239.12 is: 329.94

Step by Step Solution

  1. Step 1: Write the proportion equation
    388.40 : 535.92 = 239.12 : x
  2. Step 2: Convert to fraction form
    388.40/535.92 = 239.12/x
  3. Step 3: Cross multiply
    388.40x = 535.92 × 239.12
  4. Step 4: Simplify right side
    388.40x = 128,149.19
  5. Step 5: Solve for x
    x = 128,149.19/388.40
  6. Step 6: Final answer
    x = 329.94

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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.