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Finding the Fourth Proportional to 80.12, 119.96 and 66.65

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Solution

The fourth proportional to 80.12, 119.96 and 66.65 is: 99.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    80.12 : 119.96 = 66.65 : x
  2. Step 2: Convert to fraction form
    80.12/119.96 = 66.65/x
  3. Step 3: Cross multiply
    80.12x = 119.96 × 66.65
  4. Step 4: Simplify right side
    80.12x = 7,994.65
  5. Step 5: Solve for x
    x = 7,994.65/80.12
  6. Step 6: Final answer
    x = 99.78

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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.