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Finding the Fourth Proportional to 139.52, 209.40 and 119.12

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Solution

The fourth proportional to 139.52, 209.40 and 119.12 is: 178.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    139.52 : 209.40 = 119.12 : x
  2. Step 2: Convert to fraction form
    139.52/209.40 = 119.12/x
  3. Step 3: Cross multiply
    139.52x = 209.40 × 119.12
  4. Step 4: Simplify right side
    139.52x = 24,943.73
  5. Step 5: Solve for x
    x = 24,943.73/139.52
  6. Step 6: Final answer
    x = 178.78

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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.