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Finding the Fourth Proportional to 80.96, 120.60 and 79.90

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Solution

The fourth proportional to 80.96, 120.60 and 79.90 is: 119.02

Step by Step Solution

  1. Step 1: Write the proportion equation
    80.96 : 120.60 = 79.90 : x
  2. Step 2: Convert to fraction form
    80.96/120.60 = 79.90/x
  3. Step 3: Cross multiply
    80.96x = 120.60 × 79.90
  4. Step 4: Simplify right side
    80.96x = 9,635.94
  5. Step 5: Solve for x
    x = 9,635.94/80.96
  6. Step 6: Final answer
    x = 119.02

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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.