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Finding the Fourth Proportional to 139.79, 209.99 and 136.89

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Solution

The fourth proportional to 139.79, 209.99 and 136.89 is: 205.63

Step by Step Solution

  1. Step 1: Write the proportion equation
    139.79 : 209.99 = 136.89 : x
  2. Step 2: Convert to fraction form
    139.79/209.99 = 136.89/x
  3. Step 3: Cross multiply
    139.79x = 209.99 × 136.89
  4. Step 4: Simplify right side
    139.79x = 28,745.87
  5. Step 5: Solve for x
    x = 28,745.87/139.79
  6. Step 6: Final answer
    x = 205.63

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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.