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Finding the Fourth Proportional to 668.62, 921.24 and 499.87

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Solution

The fourth proportional to 668.62, 921.24 and 499.87 is: 688.73

Step by Step Solution

  1. Step 1: Write the proportion equation
    668.62 : 921.24 = 499.87 : x
  2. Step 2: Convert to fraction form
    668.62/921.24 = 499.87/x
  3. Step 3: Cross multiply
    668.62x = 921.24 × 499.87
  4. Step 4: Simplify right side
    668.62x = 460,500.24
  5. Step 5: Solve for x
    x = 460,500.24/668.62
  6. Step 6: Final answer
    x = 688.73

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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.