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Finding the Fourth Proportional to 499.01, 688.97 and 312.78

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Solution

The fourth proportional to 499.01, 688.97 and 312.78 is: 431.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    499.01 : 688.97 = 312.78 : x
  2. Step 2: Convert to fraction form
    499.01/688.97 = 312.78/x
  3. Step 3: Cross multiply
    499.01x = 688.97 × 312.78
  4. Step 4: Simplify right side
    499.01x = 215,496.04
  5. Step 5: Solve for x
    x = 215,496.04/499.01
  6. Step 6: Final answer
    x = 431.85

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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.