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Finding the Fourth Proportional to 80.31, 110.79 and 69.38

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Solution

The fourth proportional to 80.31, 110.79 and 69.38 is: 95.70

Step by Step Solution

  1. Step 1: Write the proportion equation
    80.31 : 110.79 = 69.38 : x
  2. Step 2: Convert to fraction form
    80.31/110.79 = 69.38/x
  3. Step 3: Cross multiply
    80.31x = 110.79 × 69.38
  4. Step 4: Simplify right side
    80.31x = 7,686.06
  5. Step 5: Solve for x
    x = 7,686.06/80.31
  6. Step 6: Final answer
    x = 95.70

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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.