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Finding the Fourth Proportional to 391.30, 584.17 and 329.78

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Solution

The fourth proportional to 391.30, 584.17 and 329.78 is: 492.33

Step by Step Solution

  1. Step 1: Write the proportion equation
    391.30 : 584.17 = 329.78 : x
  2. Step 2: Convert to fraction form
    391.30/584.17 = 329.78/x
  3. Step 3: Cross multiply
    391.30x = 584.17 × 329.78
  4. Step 4: Simplify right side
    391.30x = 192,648.22
  5. Step 5: Solve for x
    x = 192,648.22/391.30
  6. Step 6: Final answer
    x = 492.33

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.