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Finding the Fourth Proportional to 658.35, 987.87 and 427.17

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Solution

The fourth proportional to 658.35, 987.87 and 427.17 is: 640.98

Step by Step Solution

  1. Step 1: Write the proportion equation
    658.35 : 987.87 = 427.17 : x
  2. Step 2: Convert to fraction form
    658.35/987.87 = 427.17/x
  3. Step 3: Cross multiply
    658.35x = 987.87 × 427.17
  4. Step 4: Simplify right side
    658.35x = 421,988.43
  5. Step 5: Solve for x
    x = 421,988.43/658.35
  6. Step 6: Final answer
    x = 640.98

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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.