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Finding the Fourth Proportional to 55.20, 82.70 and 51.85

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Solution

The fourth proportional to 55.20, 82.70 and 51.85 is: 77.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    55.20 : 82.70 = 51.85 : x
  2. Step 2: Convert to fraction form
    55.20/82.70 = 51.85/x
  3. Step 3: Cross multiply
    55.20x = 82.70 × 51.85
  4. Step 4: Simplify right side
    55.20x = 4,288.00
  5. Step 5: Solve for x
    x = 4,288.00/55.20
  6. Step 6: Final answer
    x = 77.68

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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.