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Finding the Fourth Proportional to 80.37, 111.45 and 77.61

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Solution

The fourth proportional to 80.37, 111.45 and 77.61 is: 107.62

Step by Step Solution

  1. Step 1: Write the proportion equation
    80.37 : 111.45 = 77.61 : x
  2. Step 2: Convert to fraction form
    80.37/111.45 = 77.61/x
  3. Step 3: Cross multiply
    80.37x = 111.45 × 77.61
  4. Step 4: Simplify right side
    80.37x = 8,649.63
  5. Step 5: Solve for x
    x = 8,649.63/80.37
  6. Step 6: Final answer
    x = 107.62

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Why These Related Problems?

These problems maintain the same ratio (1.39) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.