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Finding the Fourth Proportional to 77.58, 108.09 and 77.58

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Solution

The fourth proportional to 77.58, 108.09 and 77.58 is: 108.09

Step by Step Solution

  1. Step 1: Write the proportion equation
    77.58 : 108.09 = 77.58 : x
  2. Step 2: Convert to fraction form
    77.58/108.09 = 77.58/x
  3. Step 3: Cross multiply
    77.58x = 108.09 × 77.58
  4. Step 4: Simplify right side
    77.58x = 8,385.62
  5. Step 5: Solve for x
    x = 8,385.62/77.58
  6. Step 6: Final answer
    x = 108.09

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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.