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Finding the Fourth Proportional to 85.08, 127.38 and 54.54

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Solution

The fourth proportional to 85.08, 127.38 and 54.54 is: 81.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    85.08 : 127.38 = 54.54 : x
  2. Step 2: Convert to fraction form
    85.08/127.38 = 54.54/x
  3. Step 3: Cross multiply
    85.08x = 127.38 × 54.54
  4. Step 4: Simplify right side
    85.08x = 6,947.31
  5. Step 5: Solve for x
    x = 6,947.31/85.08
  6. Step 6: Final answer
    x = 81.66

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.