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Finding the Fourth Proportional to 85.17, 127.77 and 54.77

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Solution

The fourth proportional to 85.17, 127.77 and 54.77 is: 82.16

Step by Step Solution

  1. Step 1: Write the proportion equation
    85.17 : 127.77 = 54.77 : x
  2. Step 2: Convert to fraction form
    85.17/127.77 = 54.77/x
  3. Step 3: Cross multiply
    85.17x = 127.77 × 54.77
  4. Step 4: Simplify right side
    85.17x = 6,997.32
  5. Step 5: Solve for x
    x = 6,997.32/85.17
  6. Step 6: Final answer
    x = 82.16

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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.