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Finding the Fourth Proportional to 668.20, 1,002 and 355.78

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Solution

The fourth proportional to 668.20, 1,002 and 355.78 is: 533.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    668.20 : 1,002 = 355.78 : x
  2. Step 2: Convert to fraction form
    668.20/1,002 = 355.78/x
  3. Step 3: Cross multiply
    668.20x = 1,002 × 355.78
  4. Step 4: Simplify right side
    668.20x = 356,489.06
  5. Step 5: Solve for x
    x = 356,489.06/668.20
  6. Step 6: Final answer
    x = 533.51

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.