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Finding the Fourth Proportional to 38.20, 57.27 and 19.91

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Solution

The fourth proportional to 38.20, 57.27 and 19.91 is: 29.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    38.20 : 57.27 = 19.91 : x
  2. Step 2: Convert to fraction form
    38.20/57.27 = 19.91/x
  3. Step 3: Cross multiply
    38.20x = 57.27 × 19.91
  4. Step 4: Simplify right side
    38.20x = 1,140.25
  5. Step 5: Solve for x
    x = 1,140.25/38.20
  6. Step 6: Final answer
    x = 29.85

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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.