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Finding the Fourth Proportional to 80.16, 111.17 and 77.15

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Solution

The fourth proportional to 80.16, 111.17 and 77.15 is: 106.98

Step by Step Solution

  1. Step 1: Write the proportion equation
    80.16 : 111.17 = 77.15 : x
  2. Step 2: Convert to fraction form
    80.16/111.17 = 77.15/x
  3. Step 3: Cross multiply
    80.16x = 111.17 × 77.15
  4. Step 4: Simplify right side
    80.16x = 8,575.82
  5. Step 5: Solve for x
    x = 8,575.82/80.16
  6. Step 6: Final answer
    x = 106.98

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Why These Related Problems?

These problems maintain the same ratio (1.39) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.