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Finding the Fourth Proportional to 501.29, 691.78 and 280.25

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Solution

The fourth proportional to 501.29, 691.78 and 280.25 is: 386.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    501.29 : 691.78 = 280.25 : x
  2. Step 2: Convert to fraction form
    501.29/691.78 = 280.25/x
  3. Step 3: Cross multiply
    501.29x = 691.78 × 280.25
  4. Step 4: Simplify right side
    501.29x = 193,872.90
  5. Step 5: Solve for x
    x = 193,872.90/501.29
  6. Step 6: Final answer
    x = 386.75

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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.