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Finding the Fourth Proportional to 80.39, 120.71 and 69.10

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Solution

The fourth proportional to 80.39, 120.71 and 69.10 is: 103.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    80.39 : 120.71 = 69.10 : x
  2. Step 2: Convert to fraction form
    80.39/120.71 = 69.10/x
  3. Step 3: Cross multiply
    80.39x = 120.71 × 69.10
  4. Step 4: Simplify right side
    80.39x = 8,340.41
  5. Step 5: Solve for x
    x = 8,340.41/80.39
  6. Step 6: Final answer
    x = 103.76

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.