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Finding the Fourth Proportional to 628.20, 866.66 and 395.56

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Solution

The fourth proportional to 628.20, 866.66 and 395.56 is: 545.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    628.20 : 866.66 = 395.56 : x
  2. Step 2: Convert to fraction form
    628.20/866.66 = 395.56/x
  3. Step 3: Cross multiply
    628.20x = 866.66 × 395.56
  4. Step 4: Simplify right side
    628.20x = 342,816.03
  5. Step 5: Solve for x
    x = 342,816.03/628.20
  6. Step 6: Final answer
    x = 545.71

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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.