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Finding the Fourth Proportional to 501.35, 691.89 and 280.31

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Solution

The fourth proportional to 501.35, 691.89 and 280.31 is: 386.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    501.35 : 691.89 = 280.31 : x
  2. Step 2: Convert to fraction form
    501.35/691.89 = 280.31/x
  3. Step 3: Cross multiply
    501.35x = 691.89 × 280.31
  4. Step 4: Simplify right side
    501.35x = 193,944.64
  5. Step 5: Solve for x
    x = 193,944.64/501.35
  6. Step 6: Final answer
    x = 386.85

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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.