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Finding the Fourth Proportional to 139.03, 208.21 and 122.61

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Solution

The fourth proportional to 139.03, 208.21 and 122.61 is: 183.61

Step by Step Solution

  1. Step 1: Write the proportion equation
    139.03 : 208.21 = 122.61 : x
  2. Step 2: Convert to fraction form
    139.03/208.21 = 122.61/x
  3. Step 3: Cross multiply
    139.03x = 208.21 × 122.61
  4. Step 4: Simplify right side
    139.03x = 25,527.40
  5. Step 5: Solve for x
    x = 25,527.40/139.03
  6. Step 6: Final answer
    x = 183.61

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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.