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Finding the Fourth Proportional to 77.17, 115.70 and 54.39

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Solution

The fourth proportional to 77.17, 115.70 and 54.39 is: 81.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    77.17 : 115.70 = 54.39 : x
  2. Step 2: Convert to fraction form
    77.17/115.70 = 54.39/x
  3. Step 3: Cross multiply
    77.17x = 115.70 × 54.39
  4. Step 4: Simplify right side
    77.17x = 6,292.92
  5. Step 5: Solve for x
    x = 6,292.92/77.17
  6. Step 6: Final answer
    x = 81.55

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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.