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Finding the Fourth Proportional to 391.85, 540.09 and 297.29

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Solution

The fourth proportional to 391.85, 540.09 and 297.29 is: 409.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    391.85 : 540.09 = 297.29 : x
  2. Step 2: Convert to fraction form
    391.85/540.09 = 297.29/x
  3. Step 3: Cross multiply
    391.85x = 540.09 × 297.29
  4. Step 4: Simplify right side
    391.85x = 160,562.68
  5. Step 5: Solve for x
    x = 160,562.68/391.85
  6. Step 6: Final answer
    x = 409.76

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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.