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Finding the Fourth Proportional to 501.28, 691.82 and 280.31

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Solution

The fourth proportional to 501.28, 691.82 and 280.31 is: 386.86

Step by Step Solution

  1. Step 1: Write the proportion equation
    501.28 : 691.82 = 280.31 : x
  2. Step 2: Convert to fraction form
    501.28/691.82 = 280.31/x
  3. Step 3: Cross multiply
    501.28x = 691.82 × 280.31
  4. Step 4: Simplify right side
    501.28x = 193,924.06
  5. Step 5: Solve for x
    x = 193,924.06/501.28
  6. Step 6: Final answer
    x = 386.86

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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.