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Finding the Fourth Proportional to 438.08, 658.36 and 421.92

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Solution

The fourth proportional to 438.08, 658.36 and 421.92 is: 634.07

Step by Step Solution

  1. Step 1: Write the proportion equation
    438.08 : 658.36 = 421.92 : x
  2. Step 2: Convert to fraction form
    438.08/658.36 = 421.92/x
  3. Step 3: Cross multiply
    438.08x = 658.36 × 421.92
  4. Step 4: Simplify right side
    438.08x = 277,775.25
  5. Step 5: Solve for x
    x = 277,775.25/438.08
  6. Step 6: Final answer
    x = 634.07

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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.