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Finding the Fourth Proportional to 77.20, 115.07 and 72.52

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Solution

The fourth proportional to 77.20, 115.07 and 72.52 is: 108.09

Step by Step Solution

  1. Step 1: Write the proportion equation
    77.20 : 115.07 = 72.52 : x
  2. Step 2: Convert to fraction form
    77.20/115.07 = 72.52/x
  3. Step 3: Cross multiply
    77.20x = 115.07 × 72.52
  4. Step 4: Simplify right side
    77.20x = 8,343.94
  5. Step 5: Solve for x
    x = 8,343.94/77.20
  6. Step 6: Final answer
    x = 108.09

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.