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Finding the Fourth Proportional to 643.08, 963.92 and 459.92

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Solution

The fourth proportional to 643.08, 963.92 and 459.92 is: 689.37

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.08 : 963.92 = 459.92 : x
  2. Step 2: Convert to fraction form
    643.08/963.92 = 459.92/x
  3. Step 3: Cross multiply
    643.08x = 963.92 × 459.92
  4. Step 4: Simplify right side
    643.08x = 443,318.97
  5. Step 5: Solve for x
    x = 443,318.97/643.08
  6. Step 6: Final answer
    x = 689.37

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.