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Finding the Fourth Proportional to 439.20, 657.90 and 330.66

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Solution

The fourth proportional to 439.20, 657.90 and 330.66 is: 495.31

Step by Step Solution

  1. Step 1: Write the proportion equation
    439.20 : 657.90 = 330.66 : x
  2. Step 2: Convert to fraction form
    439.20/657.90 = 330.66/x
  3. Step 3: Cross multiply
    439.20x = 657.90 × 330.66
  4. Step 4: Simplify right side
    439.20x = 217,541.21
  5. Step 5: Solve for x
    x = 217,541.21/439.20
  6. Step 6: Final answer
    x = 495.31

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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.