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Finding the Fourth Proportional to 501.31, 691.83 and 280.25

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Solution

The fourth proportional to 501.31, 691.83 and 280.25 is: 386.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    501.31 : 691.83 = 280.25 : x
  2. Step 2: Convert to fraction form
    501.31/691.83 = 280.25/x
  3. Step 3: Cross multiply
    501.31x = 691.83 × 280.25
  4. Step 4: Simplify right side
    501.31x = 193,885.36
  5. Step 5: Solve for x
    x = 193,885.36/501.31
  6. Step 6: Final answer
    x = 386.76

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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.