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Finding the Fourth Proportional to 39.69, 54.83 and 28.86

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Solution

The fourth proportional to 39.69, 54.83 and 28.86 is: 39.86

Step by Step Solution

  1. Step 1: Write the proportion equation
    39.69 : 54.83 = 28.86 : x
  2. Step 2: Convert to fraction form
    39.69/54.83 = 28.86/x
  3. Step 3: Cross multiply
    39.69x = 54.83 × 28.86
  4. Step 4: Simplify right side
    39.69x = 1,582.10
  5. Step 5: Solve for x
    x = 1,582.10/39.69
  6. Step 6: Final answer
    x = 39.86

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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.