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Finding the Fourth Proportional to 381.72, 572.82 and 219.72

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Solution

The fourth proportional to 381.72, 572.82 and 219.72 is: 329.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    381.72 : 572.82 = 219.72 : x
  2. Step 2: Convert to fraction form
    381.72/572.82 = 219.72/x
  3. Step 3: Cross multiply
    381.72x = 572.82 × 219.72
  4. Step 4: Simplify right side
    381.72x = 125,860.01
  5. Step 5: Solve for x
    x = 125,860.01/381.72
  6. Step 6: Final answer
    x = 329.72

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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.