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Finding the Fourth Proportional to 77.86, 108 and 75.09

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Solution

The fourth proportional to 77.86, 108 and 75.09 is: 104.16

Step by Step Solution

  1. Step 1: Write the proportion equation
    77.86 : 108 = 75.09 : x
  2. Step 2: Convert to fraction form
    77.86/108 = 75.09/x
  3. Step 3: Cross multiply
    77.86x = 108 × 75.09
  4. Step 4: Simplify right side
    77.86x = 8,109.72
  5. Step 5: Solve for x
    x = 8,109.72/77.86
  6. Step 6: Final answer
    x = 104.16

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Why These Related Problems?

These problems maintain the same ratio (1.39) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.