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Finding the Fourth Proportional to 501.38, 691.91 and 280.34

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Solution

The fourth proportional to 501.38, 691.91 and 280.34 is: 386.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    501.38 : 691.91 = 280.34 : x
  2. Step 2: Convert to fraction form
    501.38/691.91 = 280.34/x
  3. Step 3: Cross multiply
    501.38x = 691.91 × 280.34
  4. Step 4: Simplify right side
    501.38x = 193,972.48
  5. Step 5: Solve for x
    x = 193,972.48/501.38
  6. Step 6: Final answer
    x = 386.88

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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.