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Finding the Fourth Proportional to 80.48, 120.76 and 69.84

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Solution

The fourth proportional to 80.48, 120.76 and 69.84 is: 104.79

Step by Step Solution

  1. Step 1: Write the proportion equation
    80.48 : 120.76 = 69.84 : x
  2. Step 2: Convert to fraction form
    80.48/120.76 = 69.84/x
  3. Step 3: Cross multiply
    80.48x = 120.76 × 69.84
  4. Step 4: Simplify right side
    80.48x = 8,433.88
  5. Step 5: Solve for x
    x = 8,433.88/80.48
  6. Step 6: Final answer
    x = 104.79

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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.