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Finding the Fourth Proportional to 77.61, 107.22 and 56.89

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Solution

The fourth proportional to 77.61, 107.22 and 56.89 is: 78.59

Step by Step Solution

  1. Step 1: Write the proportion equation
    77.61 : 107.22 = 56.89 : x
  2. Step 2: Convert to fraction form
    77.61/107.22 = 56.89/x
  3. Step 3: Cross multiply
    77.61x = 107.22 × 56.89
  4. Step 4: Simplify right side
    77.61x = 6,099.75
  5. Step 5: Solve for x
    x = 6,099.75/77.61
  6. Step 6: Final answer
    x = 78.59

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.