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Finding the Fourth Proportional to 77.25, 115.89 and 25.90

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Solution

The fourth proportional to 77.25, 115.89 and 25.90 is: 38.85

Step by Step Solution

  1. Step 1: Write the proportion equation
    77.25 : 115.89 = 25.90 : x
  2. Step 2: Convert to fraction form
    77.25/115.89 = 25.90/x
  3. Step 3: Cross multiply
    77.25x = 115.89 × 25.90
  4. Step 4: Simplify right side
    77.25x = 3,001.16
  5. Step 5: Solve for x
    x = 3,001.16/77.25
  6. Step 6: Final answer
    x = 38.85

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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.