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Finding the Fourth Proportional to 501.31, 691.86 and 280.33

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Solution

The fourth proportional to 501.31, 691.86 and 280.33 is: 386.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    501.31 : 691.86 = 280.33 : x
  2. Step 2: Convert to fraction form
    501.31/691.86 = 280.33/x
  3. Step 3: Cross multiply
    501.31x = 691.86 × 280.33
  4. Step 4: Simplify right side
    501.31x = 193,949.11
  5. Step 5: Solve for x
    x = 193,949.11/501.31
  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.