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Finding the Fourth Proportional to 83.80, 115.85 and 80.17

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Solution

The fourth proportional to 83.80, 115.85 and 80.17 is: 110.83

Step by Step Solution

  1. Step 1: Write the proportion equation
    83.80 : 115.85 = 80.17 : x
  2. Step 2: Convert to fraction form
    83.80/115.85 = 80.17/x
  3. Step 3: Cross multiply
    83.80x = 115.85 × 80.17
  4. Step 4: Simplify right side
    83.80x = 9,287.12
  5. Step 5: Solve for x
    x = 9,287.12/83.80
  6. Step 6: Final answer
    x = 110.83

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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.