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Finding the Fourth Proportional to 499.20, 689.28 and 344.64

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Solution

The fourth proportional to 499.20, 689.28 and 344.64 is: 475.87

Step by Step Solution

  1. Step 1: Write the proportion equation
    499.20 : 689.28 = 344.64 : x
  2. Step 2: Convert to fraction form
    499.20/689.28 = 344.64/x
  3. Step 3: Cross multiply
    499.20x = 689.28 × 344.64
  4. Step 4: Simplify right side
    499.20x = 237,553.46
  5. Step 5: Solve for x
    x = 237,553.46/499.20
  6. Step 6: Final answer
    x = 475.87

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.