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Finding the Fourth Proportional to 80.28, 119.79 and 74.85

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Solution

The fourth proportional to 80.28, 119.79 and 74.85 is: 111.69

Step by Step Solution

  1. Step 1: Write the proportion equation
    80.28 : 119.79 = 74.85 : x
  2. Step 2: Convert to fraction form
    80.28/119.79 = 74.85/x
  3. Step 3: Cross multiply
    80.28x = 119.79 × 74.85
  4. Step 4: Simplify right side
    80.28x = 8,966.28
  5. Step 5: Solve for x
    x = 8,966.28/80.28
  6. Step 6: Final answer
    x = 111.69

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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.