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Finding the Fourth Proportional to 80.17, 120.25 and 28.80

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Solution

The fourth proportional to 80.17, 120.25 and 28.80 is: 43.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    80.17 : 120.25 = 28.80 : x
  2. Step 2: Convert to fraction form
    80.17/120.25 = 28.80/x
  3. Step 3: Cross multiply
    80.17x = 120.25 × 28.80
  4. Step 4: Simplify right side
    80.17x = 3,463.20
  5. Step 5: Solve for x
    x = 3,463.20/80.17
  6. Step 6: Final answer
    x = 43.20

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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.