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Finding the Fourth Proportional to 392.28, 587.90 and 218.85

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Solution

The fourth proportional to 392.28, 587.90 and 218.85 is: 327.98

Step by Step Solution

  1. Step 1: Write the proportion equation
    392.28 : 587.90 = 218.85 : x
  2. Step 2: Convert to fraction form
    392.28/587.90 = 218.85/x
  3. Step 3: Cross multiply
    392.28x = 587.90 × 218.85
  4. Step 4: Simplify right side
    392.28x = 128,660.82
  5. Step 5: Solve for x
    x = 128,660.82/392.28
  6. Step 6: Final answer
    x = 327.98

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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.