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Finding the Fourth Proportional to 490.60, 731.09 and 447.40

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Solution

The fourth proportional to 490.60, 731.09 and 447.40 is: 666.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    490.60 : 731.09 = 447.40 : x
  2. Step 2: Convert to fraction form
    490.60/731.09 = 447.40/x
  3. Step 3: Cross multiply
    490.60x = 731.09 × 447.40
  4. Step 4: Simplify right side
    490.60x = 327,089.67
  5. Step 5: Solve for x
    x = 327,089.67/490.60
  6. Step 6: Final answer
    x = 666.71

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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.