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Finding the Fourth Proportional to 80.12, 120.19 and 28.77

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Solution

The fourth proportional to 80.12, 120.19 and 28.77 is: 43.16

Step by Step Solution

  1. Step 1: Write the proportion equation
    80.12 : 120.19 = 28.77 : x
  2. Step 2: Convert to fraction form
    80.12/120.19 = 28.77/x
  3. Step 3: Cross multiply
    80.12x = 120.19 × 28.77
  4. Step 4: Simplify right side
    80.12x = 3,457.87
  5. Step 5: Solve for x
    x = 3,457.87/80.12
  6. Step 6: Final answer
    x = 43.16

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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.