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Finding the Fourth Proportional to 39.72, 54.87 and 34.86

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Solution

The fourth proportional to 39.72, 54.87 and 34.86 is: 48.16

Step by Step Solution

  1. Step 1: Write the proportion equation
    39.72 : 54.87 = 34.86 : x
  2. Step 2: Convert to fraction form
    39.72/54.87 = 34.86/x
  3. Step 3: Cross multiply
    39.72x = 54.87 × 34.86
  4. Step 4: Simplify right side
    39.72x = 1,912.77
  5. Step 5: Solve for x
    x = 1,912.77/39.72
  6. Step 6: Final answer
    x = 48.16

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.