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Finding the Fourth Proportional to 38.78, 57.79 and 36.61

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Solution

The fourth proportional to 38.78, 57.79 and 36.61 is: 54.56

Step by Step Solution

  1. Step 1: Write the proportion equation
    38.78 : 57.79 = 36.61 : x
  2. Step 2: Convert to fraction form
    38.78/57.79 = 36.61/x
  3. Step 3: Cross multiply
    38.78x = 57.79 × 36.61
  4. Step 4: Simplify right side
    38.78x = 2,115.69
  5. Step 5: Solve for x
    x = 2,115.69/38.78
  6. Step 6: Final answer
    x = 54.56

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.