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Finding the Fourth Proportional to 490.14, 731.66 and 428.63

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Solution

The fourth proportional to 490.14, 731.66 and 428.63 is: 639.83

Step by Step Solution

  1. Step 1: Write the proportion equation
    490.14 : 731.66 = 428.63 : x
  2. Step 2: Convert to fraction form
    490.14/731.66 = 428.63/x
  3. Step 3: Cross multiply
    490.14x = 731.66 × 428.63
  4. Step 4: Simplify right side
    490.14x = 313,605.62
  5. Step 5: Solve for x
    x = 313,605.62/490.14
  6. Step 6: Final answer
    x = 639.83

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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.