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Finding the Fourth Proportional to 80.66, 111.12 and 68.16

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Solution

The fourth proportional to 80.66, 111.12 and 68.16 is: 93.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    80.66 : 111.12 = 68.16 : x
  2. Step 2: Convert to fraction form
    80.66/111.12 = 68.16/x
  3. Step 3: Cross multiply
    80.66x = 111.12 × 68.16
  4. Step 4: Simplify right side
    80.66x = 7,573.94
  5. Step 5: Solve for x
    x = 7,573.94/80.66
  6. Step 6: Final answer
    x = 93.90

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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.