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Finding the Fourth Proportional to 77.01, 115.31 and 54.15

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Solution

The fourth proportional to 77.01, 115.31 and 54.15 is: 81.08

Step by Step Solution

  1. Step 1: Write the proportion equation
    77.01 : 115.31 = 54.15 : x
  2. Step 2: Convert to fraction form
    77.01/115.31 = 54.15/x
  3. Step 3: Cross multiply
    77.01x = 115.31 × 54.15
  4. Step 4: Simplify right side
    77.01x = 6,243.77
  5. Step 5: Solve for x
    x = 6,243.77/77.01
  6. Step 6: Final answer
    x = 81.08

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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.