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Finding the Fourth Proportional to 658.72, 987.75 and 427.72

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Solution

The fourth proportional to 658.72, 987.75 and 427.72 is: 641.37

Step by Step Solution

  1. Step 1: Write the proportion equation
    658.72 : 987.75 = 427.72 : x
  2. Step 2: Convert to fraction form
    658.72/987.75 = 427.72/x
  3. Step 3: Cross multiply
    658.72x = 987.75 × 427.72
  4. Step 4: Simplify right side
    658.72x = 422,480.43
  5. Step 5: Solve for x
    x = 422,480.43/658.72
  6. Step 6: Final answer
    x = 641.37

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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.