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Finding the Fourth Proportional to 391.16, 539.31 and 251.05

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Solution

The fourth proportional to 391.16, 539.31 and 251.05 is: 346.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    391.16 : 539.31 = 251.05 : x
  2. Step 2: Convert to fraction form
    391.16/539.31 = 251.05/x
  3. Step 3: Cross multiply
    391.16x = 539.31 × 251.05
  4. Step 4: Simplify right side
    391.16x = 135,393.78
  5. Step 5: Solve for x
    x = 135,393.78/391.16
  6. Step 6: Final answer
    x = 346.13

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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.