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Finding the Fourth Proportional to 490.38, 731.47 and 438.54

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Solution

The fourth proportional to 490.38, 731.47 and 438.54 is: 654.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    490.38 : 731.47 = 438.54 : x
  2. Step 2: Convert to fraction form
    490.38/731.47 = 438.54/x
  3. Step 3: Cross multiply
    490.38x = 731.47 × 438.54
  4. Step 4: Simplify right side
    490.38x = 320,778.85
  5. Step 5: Solve for x
    x = 320,778.85/490.38
  6. Step 6: Final answer
    x = 654.14

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.