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Finding the Fourth Proportional to 321.87, 481.90 and 206.31

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Solution

The fourth proportional to 321.87, 481.90 and 206.31 is: 308.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    321.87 : 481.90 = 206.31 : x
  2. Step 2: Convert to fraction form
    321.87/481.90 = 206.31/x
  3. Step 3: Cross multiply
    321.87x = 481.90 × 206.31
  4. Step 4: Simplify right side
    321.87x = 99,420.79
  5. Step 5: Solve for x
    x = 99,420.79/321.87
  6. Step 6: Final answer
    x = 308.88

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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.