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Finding the Fourth Proportional to 80.73, 120.42 and 72.09

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Solution

The fourth proportional to 80.73, 120.42 and 72.09 is: 107.53

Step by Step Solution

  1. Step 1: Write the proportion equation
    80.73 : 120.42 = 72.09 : x
  2. Step 2: Convert to fraction form
    80.73/120.42 = 72.09/x
  3. Step 3: Cross multiply
    80.73x = 120.42 × 72.09
  4. Step 4: Simplify right side
    80.73x = 8,681.08
  5. Step 5: Solve for x
    x = 8,681.08/80.73
  6. Step 6: Final answer
    x = 107.53

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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.