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Finding the Fourth Proportional to 77.79, 107.55 and 68.55

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Solution

The fourth proportional to 77.79, 107.55 and 68.55 is: 94.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    77.79 : 107.55 = 68.55 : x
  2. Step 2: Convert to fraction form
    77.79/107.55 = 68.55/x
  3. Step 3: Cross multiply
    77.79x = 107.55 × 68.55
  4. Step 4: Simplify right side
    77.79x = 7,372.55
  5. Step 5: Solve for x
    x = 7,372.55/77.79
  6. Step 6: Final answer
    x = 94.78

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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.