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Finding the Fourth Proportional to 138.20, 208.22 and 119.98

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Solution

The fourth proportional to 138.20, 208.22 and 119.98 is: 180.77

Step by Step Solution

  1. Step 1: Write the proportion equation
    138.20 : 208.22 = 119.98 : x
  2. Step 2: Convert to fraction form
    138.20/208.22 = 119.98/x
  3. Step 3: Cross multiply
    138.20x = 208.22 × 119.98
  4. Step 4: Simplify right side
    138.20x = 24,982.24
  5. Step 5: Solve for x
    x = 24,982.24/138.20
  6. Step 6: Final answer
    x = 180.77

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.