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Finding the Fourth Proportional to 645.09, 892.18 and 556.66

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Solution

The fourth proportional to 645.09, 892.18 and 556.66 is: 769.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    645.09 : 892.18 = 556.66 : x
  2. Step 2: Convert to fraction form
    645.09/892.18 = 556.66/x
  3. Step 3: Cross multiply
    645.09x = 892.18 × 556.66
  4. Step 4: Simplify right side
    645.09x = 496,640.92
  5. Step 5: Solve for x
    x = 496,640.92/645.09
  6. Step 6: Final answer
    x = 769.88

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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.