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Finding the Fourth Proportional to 658.92, 987.34 and 427.40

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Solution

The fourth proportional to 658.92, 987.34 and 427.40 is: 640.43

Step by Step Solution

  1. Step 1: Write the proportion equation
    658.92 : 987.34 = 427.40 : x
  2. Step 2: Convert to fraction form
    658.92/987.34 = 427.40/x
  3. Step 3: Cross multiply
    658.92x = 987.34 × 427.40
  4. Step 4: Simplify right side
    658.92x = 421,989.12
  5. Step 5: Solve for x
    x = 421,989.12/658.92
  6. Step 6: Final answer
    x = 640.43

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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.