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Finding the Fourth Proportional to 77.05, 115.56 and 56.71

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Solution

The fourth proportional to 77.05, 115.56 and 56.71 is: 85.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    77.05 : 115.56 = 56.71 : x
  2. Step 2: Convert to fraction form
    77.05/115.56 = 56.71/x
  3. Step 3: Cross multiply
    77.05x = 115.56 × 56.71
  4. Step 4: Simplify right side
    77.05x = 6,553.41
  5. Step 5: Solve for x
    x = 6,553.41/77.05
  6. Step 6: Final answer
    x = 85.05

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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.