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Finding the Fourth Proportional to 80.43, 120.05 and 69.66

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Solution

The fourth proportional to 80.43, 120.05 and 69.66 is: 103.98

Step by Step Solution

  1. Step 1: Write the proportion equation
    80.43 : 120.05 = 69.66 : x
  2. Step 2: Convert to fraction form
    80.43/120.05 = 69.66/x
  3. Step 3: Cross multiply
    80.43x = 120.05 × 69.66
  4. Step 4: Simplify right side
    80.43x = 8,362.68
  5. Step 5: Solve for x
    x = 8,362.68/80.43
  6. Step 6: Final answer
    x = 103.98

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.