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Finding the Fourth Proportional to 80.89, 111.60 and 49.79

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Solution

The fourth proportional to 80.89, 111.60 and 49.79 is: 68.69

Step by Step Solution

  1. Step 1: Write the proportion equation
    80.89 : 111.60 = 49.79 : x
  2. Step 2: Convert to fraction form
    80.89/111.60 = 49.79/x
  3. Step 3: Cross multiply
    80.89x = 111.60 × 49.79
  4. Step 4: Simplify right side
    80.89x = 5,556.56
  5. Step 5: Solve for x
    x = 5,556.56/80.89
  6. Step 6: Final answer
    x = 68.69

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.