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Finding the Fourth Proportional to 80.18, 120.37 and 79.78

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Solution

The fourth proportional to 80.18, 120.37 and 79.78 is: 119.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    80.18 : 120.37 = 79.78 : x
  2. Step 2: Convert to fraction form
    80.18/120.37 = 79.78/x
  3. Step 3: Cross multiply
    80.18x = 120.37 × 79.78
  4. Step 4: Simplify right side
    80.18x = 9,602.52
  5. Step 5: Solve for x
    x = 9,602.52/80.18
  6. Step 6: Final answer
    x = 119.76

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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.