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Finding the Fourth Proportional to 381.90, 571.49 and 330.72

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Solution

The fourth proportional to 381.90, 571.49 and 330.72 is: 494.89

Step by Step Solution

  1. Step 1: Write the proportion equation
    381.90 : 571.49 = 330.72 : x
  2. Step 2: Convert to fraction form
    381.90/571.49 = 330.72/x
  3. Step 3: Cross multiply
    381.90x = 571.49 × 330.72
  4. Step 4: Simplify right side
    381.90x = 189,001.52
  5. Step 5: Solve for x
    x = 189,001.52/381.90
  6. Step 6: Final answer
    x = 494.89

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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.