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Finding the Fourth Proportional to 80.90, 112.31 and 76.04

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Solution

The fourth proportional to 80.90, 112.31 and 76.04 is: 105.56

Step by Step Solution

  1. Step 1: Write the proportion equation
    80.90 : 112.31 = 76.04 : x
  2. Step 2: Convert to fraction form
    80.90/112.31 = 76.04/x
  3. Step 3: Cross multiply
    80.90x = 112.31 × 76.04
  4. Step 4: Simplify right side
    80.90x = 8,540.05
  5. Step 5: Solve for x
    x = 8,540.05/80.90
  6. Step 6: Final answer
    x = 105.56

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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.