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Finding the Fourth Proportional to 80.36, 120.05 and 66.12

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Solution

The fourth proportional to 80.36, 120.05 and 66.12 is: 98.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    80.36 : 120.05 = 66.12 : x
  2. Step 2: Convert to fraction form
    80.36/120.05 = 66.12/x
  3. Step 3: Cross multiply
    80.36x = 120.05 × 66.12
  4. Step 4: Simplify right side
    80.36x = 7,937.71
  5. Step 5: Solve for x
    x = 7,937.71/80.36
  6. Step 6: Final answer
    x = 98.78

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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.