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Finding the Fourth Proportional to 391.10, 539.09 and 308.07

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Solution

The fourth proportional to 391.10, 539.09 and 308.07 is: 424.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    391.10 : 539.09 = 308.07 : x
  2. Step 2: Convert to fraction form
    391.10/539.09 = 308.07/x
  3. Step 3: Cross multiply
    391.10x = 539.09 × 308.07
  4. Step 4: Simplify right side
    391.10x = 166,077.46
  5. Step 5: Solve for x
    x = 166,077.46/391.10
  6. Step 6: Final answer
    x = 424.65

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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.