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Finding the Fourth Proportional to 643.64, 963.84 and 426.56

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Solution

The fourth proportional to 643.64, 963.84 and 426.56 is: 638.77

Step by Step Solution

  1. Step 1: Write the proportion equation
    643.64 : 963.84 = 426.56 : x
  2. Step 2: Convert to fraction form
    643.64/963.84 = 426.56/x
  3. Step 3: Cross multiply
    643.64x = 963.84 × 426.56
  4. Step 4: Simplify right side
    643.64x = 411,135.59
  5. Step 5: Solve for x
    x = 411,135.59/643.64
  6. Step 6: Final answer
    x = 638.77

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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.