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Finding the Fourth Proportional to 391.05, 539.41 and 308.03

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Solution

The fourth proportional to 391.05, 539.41 and 308.03 is: 424.89

Step by Step Solution

  1. Step 1: Write the proportion equation
    391.05 : 539.41 = 308.03 : x
  2. Step 2: Convert to fraction form
    391.05/539.41 = 308.03/x
  3. Step 3: Cross multiply
    391.05x = 539.41 × 308.03
  4. Step 4: Simplify right side
    391.05x = 166,154.46
  5. Step 5: Solve for x
    x = 166,154.46/391.05
  6. Step 6: Final answer
    x = 424.89

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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.