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Finding the Fourth Proportional to 391.72, 589.32 and 330.28

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Solution

The fourth proportional to 391.72, 589.32 and 330.28 is: 496.89

Step by Step Solution

  1. Step 1: Write the proportion equation
    391.72 : 589.32 = 330.28 : x
  2. Step 2: Convert to fraction form
    391.72/589.32 = 330.28/x
  3. Step 3: Cross multiply
    391.72x = 589.32 × 330.28
  4. Step 4: Simplify right side
    391.72x = 194,640.61
  5. Step 5: Solve for x
    x = 194,640.61/391.72
  6. Step 6: Final answer
    x = 496.89

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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.