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Finding the Fourth Proportional to 77.70, 106.96 and 67.28

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Solution

The fourth proportional to 77.70, 106.96 and 67.28 is: 92.61

Step by Step Solution

  1. Step 1: Write the proportion equation
    77.70 : 106.96 = 67.28 : x
  2. Step 2: Convert to fraction form
    77.70/106.96 = 67.28/x
  3. Step 3: Cross multiply
    77.70x = 106.96 × 67.28
  4. Step 4: Simplify right side
    77.70x = 7,195.57
  5. Step 5: Solve for x
    x = 7,195.57/77.70
  6. Step 6: Final answer
    x = 92.61

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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.