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Finding the Fourth Proportional to 81.94, 123.17 and 67.05

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Solution

The fourth proportional to 81.94, 123.17 and 67.05 is: 100.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    81.94 : 123.17 = 67.05 : x
  2. Step 2: Convert to fraction form
    81.94/123.17 = 67.05/x
  3. Step 3: Cross multiply
    81.94x = 123.17 × 67.05
  4. Step 4: Simplify right side
    81.94x = 8,258.94
  5. Step 5: Solve for x
    x = 8,258.94/81.94
  6. Step 6: Final answer
    x = 100.80

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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.